Denny, the plain old screen door spring from a hardware store should be sufficient to do a test run, even if you have to splice in a short extension to match the circumference of the drum. Any sort of damper around the drum that will interrupt the harmonics should be sufficient to minimize the squeal, and if it works, maybe you can source a piece of bulk spring and make one that's exactly the right length. One item that comes to mind would be a piece of a spring-type drain cleaner snake, cut to the right length to wrap around the drum with a little stretch to keep it in place.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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