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The part # is in my old post above.Kawasaki 11060-1330 You can find them from several sources. I just found one on amazon.https://www.amazon.com/CALTRIC-Exhaust-KAWASAKI-11060-1330-11009-1680/dp/B01DYR4UGA.
Went over this a bit: http://stelviontx.blogspot.com/2015/07/exhaust-gasket-replacement-somewhat.html