This would certainly do, but a bit pricey

It's tat but I quite like it! Wonder what sort of engine would fit in there?

A group B spec 130LR if you sort out the cooling. or a similar spec but 8 port alloy head 136 Felicia MPi on bike throttle bodies and decent 3d mapable fueling/ignition.

Should be good for about 130BHP reliably with the right cam, rover V8 valve springs, porting and lightened/balanced to rev to 8k like the rally engines. All the Skoda bits mix and match, and the once factory group B parts are now made by the same engineers from their own small backstreet enterprises, when Skoda Motorsport just become part of the big VAG machine instead of having it's own shed on the old Mlada Boreslav campus, and they got laid off. The factory got 150BHP out of them on carbs. They could strip down and rebuild each night, but tbey did need to be strong as parts from behind the then Iron Curtain could take 6 months to arrive. It was basically thrash, strip, hope, clean, refit, thrash for the whole western part of the international season.