Have you tried Redrose for parts?
http://www.redrose-retrobikes.co.uk/ I just had a few bits off the Laverda I'm restoring chromed, I used
Quality Chrome in Hull who weren't cheap (£120 for a set of Jota bars, 2 big fork/headlamp brackets and chain adjustors) but the job seems good. It takes a while though, 3 -4 weeks!
I've got another few items to do and may use
RS Chrome in Manchester to see how they compare.