Hi
Sounds like fun! I would look to buy at Auction to try and get more for the money. What about a Vauxhall Frontera? Or a Daewoo Espero (its a Vauxhall under the badge, so parts are no problem, its reliable and its one of the cheapest brands on the market).
There are also Ford Mondeos on the market for that - they will be more reliable than a Granada. You could also consider an Audi 80.... I could go on forever....
It's best to search Autotrader's under £500 selection