Thats 30 mm or 1.1811 inch spacing. The stud spacing on my 66/80cc 2-stroke is: 41.275 or 1.625 inch spacing.This heavy duty muffler gasket fits most 66/80cc and 48cc 2-stroke and 4-stroke engine kit mufflers with 30mm stud spacing.
http://www.bikeberry.com/heavy-duty-muffler-gasket.html
Where do you get those ??I rarely look for anything less than a 10 pack so they're under or at a buck apiece.
Any luck yet with the gaskets ??if/when I find some, I'll let you know where they are