Thanks for the feedback. I kept the question generic to solicit the widest feedback. Specifically, there's a set of FH silencers currently listed on eBay for GBP90 (minimum bid). I'll likely try my luck as that's a substantial saving on supplier list of GBP150.

Looking for comments good and bad from anyone who has experience with the "Made in England" silencers as sold by the Classic Bike Shop (classicbikeshop.co.uk)? Are they a good supplier to deal with? Much appreciated, Garth