I'm thinking about a small project for which I would need an enclosure for a remote ballast (magnetic with capacitor and ignitor) for 50w MH lamps. Ballast-to-lamp distance would be quite short (less than 4 feet). This needs to be weatherproof. Any ideas on what I could use as a proper remote ballast enclosure is not readily available at the moment ? Thanks for your responses.

What material? PVC, Aluminum, Iron, I assume plastic would be fine?

Big connection box or electric panel box ?

Also if you use superimposed ignitor you can place it with the lamp and not with the ballast, then the cable run between them is unlimited in length and is not exposed to ignitor voltages

I'm looking for a metal enclosure that would house ballast, capacitor and ignitor. Ideally it should be around 6x6x4 inches or 15x15x10 cm. It must be weatherproof, though.

So why not connection box or panel box made for outdoors ?

I have a 35w PSMH outdoor ballast box that is in some sort of NEMA enclosure. Here is a 70w version with a larger enclosure.

http://www.ebay.com/itm/Kichler-15MHS70AZT-HID-Landscape-120V-Ballast-70W-Single-MH-Architectural-Bronze-/172119127688?hash=item2813197688:g:GyUAAOSwx-9W1bqc