It's quite hard to get the nice plain black vinyl in the UK. Happ sell it but it will cost you a bomb. It is worth noting that their stuff is really thin, so you still need to prepare the surface of your CP so it is nice and smooth.
I have read good things about arcadeprintshop at UKVAC, so I would give them a shout. You could have some nice art printed instead of plain black too. I believe they can do nice laminated CPO's, so will be a bit thicker than plain vinyl.