I paid $200 a tyre but the sizes are limited. My car is pretty light at 970kg so it is not that hard on the tyres.
You can check with Alan at ZCar, I know I guy up here who runs the 16" tyres on a SC and he seems pretty happy with the grip. I don't think they are as good as the Dunlop Formula R D01J but they are half the price.
ZCar
http://www.zcarworkshop.com.au/Newsite/home.html stock them.