Dont need a new one!!! Worked it out, after stripping it and cleaning out the rock hard grease from around the gears, cleaning the copper commutator and magnet contacts, put it back in the car, didnt work, lost my rag and whacked it!!!, it then started to work a bit, turns out the elastic band that holds the magnets against the commutator had lost its "elasticness".
Like I have said before, cheap nasty Volkswagens, that elastic band only lasted 57 years -RIP OFF!!!!