In December's issue of Performance VW yhere was an article about a company called Fat Wheels in Sheerness, Kent. They specialise in split rim wheel refurbishment, offer a collection service, will loan you a set of wheels while yours are being refurbished, and prices start from £80 per wheel for split rims.
Might be worth checking them out. I will be giving them a call in the new year as my own GTi alloys need a Refurb!
http://www.fatwheels.net