850 engine build

Norton engines are not really hard to work on. I suggest you buy the necessary tools and a factory manual and work on it yourself. The club has good DVD or VHS on rebuilding a Commando engine by Mick Hemmings, that would be worth watching. If you insist on somebody else building your engine, Mick Hemmings would be a good choice - he is in Northampton.

I agree with Colin (above) that the Commando engine is not particularly hard to work on, and that if you follow the workshop manual a successful rebuild is within the capability of the careful home mechanic. However, I do think that taking on a stripped engine in 'box of bits' form is a bit more tricky as you can't be sure the parts belong together or will fit. I would want to measure a lot of those parts to make sure they'll fit as they should. Also, if the cam followers have been removed from the cylinder block they should not be re-assembled unless you're sure they are mated to the cam lobes that they have 'bedded' into, otherwise the result is 'galling' and the camshaft will quickly wear out. If you don't have the confidence to deal with such issues, or simply don't have the time to do it yourself, I agree that Mick Hemmings would be a very good choice. But there are many other good Norton mechanics out there, both pro and amateur. If you go to your local NOC branch meeting and ask, you'll soon be pointed in the direction of the most knowledgeable mechanics in your area.