We made a small handful for these intakes out of unused exhaust headers.  Trimmed up and ready to go.  They are close to fitting Puch, Minarelli, and Morini. Probably fits or almost fits anything with a 2 bolt intake.  You will need to dremel out the mounting holes depending on the spacing on your cylinder.

20mm ID so it would be great for a spigot mount Dellorto PHBG.

36.25mm on center between the holes