not dissimilar to my new project, and in much the same condition by the look of it. took delivery this morning
I don't think phil's got much if anything 2 stroke benelli any more. parts bare going to be interesting, but US ebay will be very helpful. Cosmo in the US had/have lots of NOS stuff, but they've been selling it off in job lots lately and it's then appearing regularly from various ebay sellers.
I think the down pipe's about 74/5 and the up pipe 76. I'll have to consult my Benelli book. I have a mate who bought one new as his first bike.