Glad I'm not the only one who thinks 170 quid is beyond extortionate! Well I guess the next step is contact VW UK and seeing what the crack is. If there's evidence to suggest that the plaque has been issued already then I would expect to pay a 're-issue' fee of around 20 quid, as all it is, essentially, is a piece of stainless steal with a number printed on it. However from the way VW Norwich were talking suggested it has never been issued to the car, therefore making it free?
I must say dealers do make me laugh because if you buy a brand new 'expensive' car they can't do enough for you, as when I bought a Scirocco back in Jan '09, buy a approved used car and they don't care. They don't seem interested at all.
That said I still remain confident that good ones still exist.