The Blue bike's monoshock swingarm & tranny cradle are one-off, custom built by Kenny Dreer when he FIRST prototyped the "new" Norton Commando 952. He later settled on the twin shock/961 that he eventually sold all rights to, to Stuart Garner in the UK. (they are now FINALLY in production for 2010 release)
The '74 850 I'm building uses an entirely new design that I prototyped and fabricated right here in my humble shop.
Here's the current mock-up (front wheel is NOT what will be used, it willbe just like the Blue bike)-