I've just had a quick look at pistonheads and the average price there is about 3k. Basically you've bought a project car, which for £1500 is about right. You haven't mentioned anything about the turbo, but I'll bet it was running 1bar in which case it was probably making about 270 bhp. To get another car like that with a similar spec and no rust will easily be 3k+. however you could buy one for cheaper which had rust. If I was you I'd get a rolling shell and swap all the parts over. If the engine and mechanicals are fine then for another £700 you'll have a decent car, coupled with the satisfaction that you've done it yourself. As long as the shells solid you can sort any minor niggles at a later date.