your not going to have much choice about not going to VW.
As their parts system is so incredibly complex, not many offer its range in its entirety. Unless its a pretty common part (the description above doesnt suggest it is a common part) you wont find many other manufacturers making an equiv part.
TPS (trade parts service) can supply the full line of VW parts (all genuine) but its unlikely to be less than 10% cheaper than VW themselves.
TPS are very good in my experience though