2004/53 plate
in that case, you're actually looking at a major service, as well as cam belt (4 years), brake fluid charged (4 years)
I think there are quite a few other bits, that i'd have to check the manual for, but i wouldn't expect much change from £500 given the VW prices.
when you take it in, i'd speak to them and check to see if yours should have been switched to fixed being a PD, as the fixed and variable use different oils, and AFAIK all the PDs should now be on fixed ie every 10K