I am about to buy a lamp,ballast,ingniter,capacitor. does anyone know what capacitor i would use for a 66 watt sox-e ballast,lamp etc?
the ballast is a:BSX 66 Watt H66 240V 50Hz CW-173/52 SOX Ballast
the ignitor is a:SX76 66/90W SOX Ignitor 220-240V 50/60Hz
WHAT IS THE CAPACITOR

A SOX-E 66W lamp requires a 7.7uF/300VAC capacitor  in conjunction with a BSX90H26 CWA ballast and SX70 igniter (source: Philips pocketbook 87/88).

See also pag 68/69: http://www.italux.pt/appl_guide_hid.pdf

You could also use an HF electronic ballast for this lamp: the EXC66 SOX-E:

http://download.p4c.philips.com/l4b/9/913700621766_eu/913700621766_eu_pss_aenaa.pdf

I can not find a 7.7 UF capacitor 300V

I can not find a 7.7 UF capacitor 300V

You can assemble a parallel bank of 300..350VAC rated capacitors, where the sum is the required 7.7uF. The CWA ballast uses the capacitor as the main impedance, so the total capacitance have to match.

Would a 5,6,7,8 etc UF capacitor work?

Would a 5,6,7,8 etc UF capacitor work?

As alone the 5 and 6 won't, the 7uF will yield too low, 8uF too high lamp current.

So you may combine:
5+2.7
or
6+1.8 (this would be slightly above, but still well within the tolerance)
or
7+0.68 (this would be slightly below, but still well within the tolerance)
or
other combination yielding the 7.7uF +/-5% including component tolerances.

7.5 uf cap is pretty common value. Problem is here in the USA it is hard to find those odd value caps
 The good new American caps have 10 to 20 percent tolerances  meaning, there a chance of finding caps that
Are underrated  8uf. Is not that far off from 7,7
I got two srs ballast I am testing out soon as i test those .odd value caps not existant here unless u Cob up a few caps together.

7.5 uf cap is pretty common value. Problem is here in the USA it is hard to find those odd value caps

I got two srs ballast I am testing out soon as i test those .odd value caps not existant here unless u Cob up a few caps together.

You are talking about porting those ballasts from 50Hz to the 60Hz area?
Then be aware, that mean at least virtually complete redesign of the circuit or it will not work at all (the required tolerance window would tighten, so even the tolerance of the ballast itself could become way too wide, or the voltages or currents would become too far from the specification,...)
So porting just a series inductor is quite troublesome (need for odd supply voltages,...), porting something like CWA I see as nearly not possible.

The good new American caps have 10 to 20 percent tolerances  meaning, there a chance of finding caps that
Are underrated  8uf. Is not that far off from 7,7

For 10% tolerance it is not that far off, but the 10% is intended only for power factor correction or motor phase shift, but it is usually too wide for the ballasting impedance in a lamp ballast. The problem is, in a CWA style ballasts the overall ballasting impedance is a difference Xc-Xl, where the Xc is more than twice of the Xl, so 5% change of the Xc would mean more than 10% change of the total ballasting impedance, without the current stabilizing effects. The current stabilizing effect of the CWA concept usually reduce the spread by about factor of two, so back to the +/-5%. But this extra 5% then sum up with the other variables (mainly mains voltage) and you may easily end up outside the rated lamp current tolerance window.

The 20% would be way too wide.

It is not as much about the manufacture tolerance, but more a window for the capacitor wear, mainly with the "selfhealing" types. Initially the capacitance is intentionally made close to the upper end of the tolerance window, but as the capacitor is exposed to nasty spikes over it's life and the selfhealing have to act, the capacitance reduces.
And the whole thing is calculated so, the capacitance drop to the minimum end of the tolerance window just at the end of it's rated life.
So installing them on places requiring tighter tolerance window mean shorter life (less of the shift mean the value goes out of the allowed tolerance window)

And

I can only find standard capacitors. I am ordering them from the U.K. I need a new solution.

Sorry, you haven't specified in the profile your location, so Ican notgive more than the generic knowledge.
Where do you want to operate the fixture?
On 230..240V/50Hz (EU,...) or 120V/60Hz (US,...)?

I live in Portland oregon U.S.A. But I use the 220-240 volts since i once lived in the United kingdom. i do have a heavy duty transformer.

The transformer won't help you.
The problem is, the UK ballasts isdesigned to operate on 50Hz, but in the U.S. you have 60Hz. And except resistive and/or electronic ballasts, all others are frequency sensitive.
So in theoretically it would mean complete ballast redesign (with the limitation to not physically modify some of the components). And that mean the necessity to know exactly, how it works, be able to do the related math, what exactly the lamp need and then a lot of experiments.

Some simpler ballasts are possible to adopt (e.g. with theseries choke use higher supply voltage,...), but the CWA is quite complex concept. As the core&coil part perform three functions, keeping all these working after the conversion I see as not possible.

Practically the ballasts from the UK are unusable for you, you have to find the US equivalent.

the transformer prouduces 220-240v 50-60hz.

the transformer prouduces 220-240v 50-60hz.

The label rating does not mean it "produce" that frequency/voltage, but it is rated for such frequency/voltage.

The transformer produces only the frequency it get on it's input, it can not change it.
So if the input is 50Hz, the output is 50Hz.
If the input is 60HZ, the output is the 60Hz as well.

And the transformer changes the voltage according it's conversion ratio, which is usually fixed.
So if it is rated "110-125V/220..250V" it mean, than it multiply the voltage by two, so will produce 220V from the 110V feed and 250V from the 125V feed.

A nice way to circumvent the frequency dependency is the use of an electronic ballast instead; e.g. the Philips EXC066 SOX-E 220-240V.

http://www.ecat.lighting.philips.com/l/oem/hid-systems/electronic-drivers-outdoor/exc-for-sox/913700621766_eu/