Hi David,
In addition to the one mentioned above (it was an ok driver, not great), I have seen 3 other GTCs for sale in the last 6 months. They were all quite nice cars but I'm not sure if they are still available:
1) met. grey / red LHD in Peru $40k USD
2) yellow / grey RHD in France 38k Euros
3) blue / grey LHD in UK 30k Pounds
So, I'd say $40k+ is the top. Basket cases (of which there are several around) seem to go for over $10k if the pieces are there.