Rear brake cylinder part no.

Hi guys just wondering if anyone knows the part no. For the rear brake cylinder on a 1990 1.8 clipper cabriolet. There seems to be a few different parts & I can't really get much info from the seller. Also, I put new shoes in last year, & have only ran them for about 100 miles, but my cylinders have been leaking & they've got fluid over them. Can I just give them a good clean (if so what's the best thing to use) or do I need new shoes.
Thanks

Depends on whether you have a regulator fitted or not also there will likely be a choice of steel or ali too.

http://www.vwspares.co.uk/g1brakes.php