Buy another head, strip it all down and de-coke it. Let a shop skim it for you (£40-50) and do the rest yourself
Seals are just push pull off - push on.
valves seal themselves - they never came out the factory new carbonised up did they
Buy a lapping tool and paste (£5)
throw new head on the car with new gaskets etc
sell old head to recoup some monies
It means you have your car off the road for less time, its what i did for my vr6
Dont forget to buy headbolts.. youll probably need the right spline tool too, is it getting expensive yet?

I dont know how you time a 1.8t up so thats upto somebody else to shed some light