On Saturday, July 4, 2020 at 11:15:50 PM UTC-4, David Cleveland wrote:
Do any of you tow guys out there know where to find a muffler for a CallAir A9-B?

I'm pretty sure the exhaust system is the same for either engine that came with the A-9B. It's probably the same for the A9-A as well, but I'm not sure. This particular airplane has a Lycoming IO-540-G1C5.

Call the guys at Plane Exhaust in Ft. Lauderdale, they are the experts, simply the best in the business.