Yes to special, in tbat they were homologation issue often. Production based race series dictated limited modifications to factory production line vehicles and usually a minimum number available for public sale. These type of "special" vehicles were the result, with enhanced elements that would be useful to racing modifications, whether used on road vehicle or not.
Quite valuable now as they are the desirable limited run specification. Probably in the region of £50,000 upward for one of those if genuine manufacture with traceable records etc.
13" wheels do look quite small now against general modern stuff. F1 was still on 13" until 2021 though, with small rim and big tire being considerably lighter than the current 18" they've moved to.
