Hello Chris
Replaced rt hand motor on my S1 a couple of years ago. Bought the replacement part from BHM (eg Morgan part) for about 170€. Not that cheap but at least when it comes to fitting probably the easiest window winder mechanism i have ever had to access (no nasty breaking clips!)
If you do the job have a look at the top pulley, on mine it was not turning due to a poor spot weld on the frame, and hence the cable frayed.
Cheers
