I think you'll find that the reason there's no mass-market PV's that are not made in China is due to the lower labour costs in China.
I mean, a UK producer would have to pay his staff the minimum wage - what would this do to the final cost of the product? Would you pay 150 quid for something like the Lavatube? No? How about sixty quid for an Ego?
EDIT: Of course, there ARE plenty of US and UK
mods being hand-built in small quantities - which tends to keep the price high. What kind of thing did you have in mind?