Just get it from a VW dealer (parts) - they stock their quantum oils, and you can be sure its exactly the right spec for the car - while your at it get the oem oil filter, and new sump plug washer too.
Failing that get a good fully synthetic 5w30 oil that meats vw spec (mobil 1 long life stuff shd be good). Some members use 5w40 on higher milage cars like yours but given the cold weather I would stick with the thinner 5w30 (or 0w30 even)
ps if you do a forum search on this im sure plenty of threads would come up...
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