The UK has some advantages then. I always fancied a GTM Coupe
or the more modern version, the Libra.
Both are glassfibre and mid engined using the parts from either a Mini (i.e. the original one) for the Coupe or a Metro (Rover style, not Geo) for the Libra. The latter has the option of a nifty injected 1.1 or 1.4 8v right up to 1.8 vvc or even a V6 if you feel brave enough.
Or (just found this) how about a Pelandini from Australia
Other alternatives at the
Mini Marcos site.