Yeah, some antique malls are good places to look for this sort of stuff too. I once found a new 1000w H36 Philips BT-56 lamp at a antique mall.

There's a GE sun lamp with fixture & box for $15 at the local antique mall . No idea if it works though.

I've seen them before in thrift stores like Savers. Usually still installed in the fixture.

 I'd check eBay . Sometime they show up rather cheap .

My #1 (if I could only choose ONE) favorite would, hands-down, have to be my GE LMSFL-70 Miser HPS Flood.   

My 2nd would be my NOS Philips 18W Mini-SOX wallpack. 

Both can be found in my gallery if you haven't already seen them. 

No problem, looking back at the records we paid £74 for our Gamma 6 in 2019. The ballast in it was as rusty as hell so needed replacing, fortunately I had a compatible spare, otherwise it would have been more money still. The Beta 5 was cheaper, but needed a fair amount of work including rewiring.

Best of luck, anyway 

Thanks for the info

I think you'll have trouble at that price. $75 Australian is just over £42 sterling; the cheapest I can find any Thorn fixtures on UK eBay is £60 + £12 shipping for a top-entry Beta 5.

For lamps, you're looking at a minimum of £15 for a used 35W, new ones start at double that at a minimum.

With respect, I think you are going to have to be prepared to pay a little more.

The Sylvania one I had in my other MV tanning fixture (not posted here) went bad. I guess it was just barely hanging on. 
It needs to have a mogul base, not a medium one.

Welcome! I visited your website before, the pfd with the Philips catalogue was really helpful in finding information on lamps and my older SORA fixtures. Bedankt!