1976 Kawasaki h2 race chambers. Looking for muffler

I am putting an h2 back on the street. I am looking for end muffler. Anyone know a good source I measured it and i Think it is 21mm. I posted a picture.

 

If you can’t find anything else these are cheap enough you could probably have a machine shop make a sleeve or a new connecting piece of the proper i.d.?

https://www.amazon.com/Universal-Mo...t=&hvlocphy=9031546&hvtargid=pla-887879851908

 

Most 3 bolt 2T mufflers are 'close' to each other.
You will have to cut back the pipe protruding past the flange a bit if the ID is different.
Otherwise they will bolt up. Decent ones like Tyga or ChingChow's from Amazon/Ebay will fly...