Imo you would have to be very lucky to find a "decent" one for that kind of money and it would probably involve traveling from one end of the country to the other. you could probably get one with tidy (ish) bodywork but smokey engine and tired mechanicals for that amount. Just depends if you want to buy a car and have to spend money on it straight away. Personally I would look to pay £2500-£3000 for a nice one that wont need money spent on it straight away.

I sold a red 1991 H plate about 6 months ago with a blown engine but ok bodywork mot,tax etc for £800. To put things in perspective.

That said there are bargains to be had, just depends how long you are willing to wait and how far you are prepaired to travel...