What’s wrong with your existing unit? Assume it’s shell damage?
Your best, most economic option would be to buy a cheap headlight (so any pre facelift) cut it open and swap all your internals (assuming that’s your issue).
Due to the ballast the internals are different so you can’t just swap the projector to make it work. You’d have to fit all the xenon specific wiring, igniter, etc.
PM me if you want. I could probably help make the Frankenstein xenon if you want? Some people not keen on headlights that have been opened, but the flip side is you’re not going to have to pay £800+ like you said.