About 5 miles from me in doncaster is a company called mx-5 city.
all cars are imported from japan and will be badged as Eunos Roadsters, don't worry about this....most insurers insurers, including tesco, will rate an inmported eunos roadster the same as a uk spec. In japan they don't use salt on the roads either so all cars are rust free. Plus they get cheap deals over there and regularly replace cars. my frined purchased a j-reg with 28k miles on the clock.
Another frined purchased one and he's more than happy with it.
http://www.mx5city.com/
all cars are 'as purchased'
once you've decided which you'd like they give it a 100 points check, valet the car, tax test the vehicle. Replace the tyres, the headlight alignment and the cloth roof (your choice of colour) they also provide the clear light conversion for the rear, the chrome packs are also available as well.
I don't work for them but on both occasion when frineds have bought a car myself and my mechanic mate who went with them for the purchase were very impressed with the level of service.
Hope this helps