Yet another reason why I love Goodwill! Found this there today, and it appears to be in playable condition.
And yes, I was in the market for a turntable anyway.
If you are jonesing for a copy yourself, there do seem to be a number on Amazon (Mickey Mouse Disco). Or if you just want to read more about this tour de force of 1979 double-platinum wackiness from Disneyland Records, Wikipedia’s got what you need.