minichamps do good ones and are the only one i know of.
there is a 1/43 scale one on amazon at the mo and a btcc lui one for £132. that is all there is online at the mo. took ages to get mine
modelzone come up trump sometimes too but they say they are no longer online and discontinued 1/18th wise but there are a few 1/43 there by the looks of it. wait around on ebay and they will turn up, sooner or later.
sorry fella.