1, I don't think there's that many in the UK, if someone could do a DVLA check I'd be surprised if the numbers were more than 4 figures.
2, Look at any desirable (modern) collectors cars, like various 911's, TVR Cerbera & Griffith, Lotus Elise & Esprit and BMW M cars, the mint stock stuff always command a premium over the spack chariots with bodykits and anything with any engine fettling has to have been built with the right parts and built by the right tuner/garage.
3. On the money.
4. Not as much as you'd think, on PH people think they are barges that don't handle and only good for motorways. I've seen "what car?" threads run to 20 pages with the Supra matching the OP's criteria to a tee but never mentioned once and if they are they are dismissed straight away. Start a thread and see for yourself if you wish.