Fix it once and fix it right; get the genuine vw repair kit and that is the best solution. You need to use the tried, true solution; that we all have used here, what the vw dealers do, using factory vw service parts (most of us have all been down this road; long term owners, have had their regulators replaced/repaired multiple times). The repair kit; comes with all the parts that break, fail and will get your beetle back to a reliable door regulator and the most reliable parts you can buy. You can purchase these online or call your local VW dealer and they are usually in stock, since they are so failure prone.
Getting the genuine vw quality parts; will actually save you time and money, in the long run.
Here are a couple of online VW parts dealers; the you can check out, to find the correct part #'s and you can use those part #'s to search for better prices (vwparts2go typically has some of the best prices out there).
www.vwpart2go.com
VW Parts | Volkswagen Parts