1272cc heads are basically the same yes. If you get one from any 1.3 mk3 polo (CL, GT, G40 etc...) then the casting is the same. The head from 1.3 engines with a carb (polo m2, golf mk2 and the jetta one you have) are pretty much the same but have a hole to drive the mechanical fuel pump, you could block this hole up with a plate though easily enough.