For the money you want to spend i think you will be looking at an import, but even the uk car prices are suffering badly at the moment.
03-05 models had the 276 bhp engine.
06 models and GT4'S had the 296 bhp engine, the very latest model as the 309 bhp engine but this would be well out of your price range.
Overall there is not an awful lot of difference between the models.Pity you did not get last months evo magazine as it had a buying guide.
Reliability overall is very good, there are a couple of issues to look for which you can find if you do a search.