You can try Darren at VW Airfix (Stanley Park Road, Wallington/Carshalton)
Steve at South London VWs (next to Dingwall motor auctions round the back of beddington Asda)
Phil at Brickfields
*edit* give empi power (Rob) a shout he could probably sort it for you but I think he is away this weekend
All pretty local to you. If I had some spare time I would come over and have a look but I am a bit snowed under at the minute. If you get really stuck give us a shout and I will see if I can come over and have a look, at worst you can always come over and borrow some tools if you need to.
Have a search through the mech tech forum, you could probably find the solution in there.