The CTR doesn't have clutch issues as such (They can 'whir' when cold, on a cold morning - but nothing ongoingly serious AFAIK). The car's party piece/form of enjoyment comes from shifting/downshifting. This will naturally deem the clutch susceptible to wear, as you'd expect.
I was lead to believe that an OEM clutch is around £200 or so.. highly doubt that is fitted price.
Perhaps not a Prem, but I think it is very possible to pick up something tidy for approx. £7k with good mileage - patience is the biggest key.
Don't be afraid to buy from an enthusaist: Whilst they will enjoy the car, they will almost certainly have maintained it to the highest standard - that said don't confuse Chav's for Enthusiasts and vice-a-versa.. two very different types, with very different ideas of what you're likely to get for a "Mint example".