Hi mate welcome to S.O.C
I think anything around the that price would need a fair bit of cash throwing at it engine rebuild that type of thing, but you never know I guess seen that happen with £5,000 cars. I've seen some classic shape wagons going for around that price that have had high milage. With a subaru I'd be looking at around £1,000 to £1,500 mark as a project car in all honesty I think you could get a pretty good one by looking around and maybe traveling further than you would normally helps. Unless you are lucky and have a few with in the area of good quality for the money :)