Tommy,
Thought maybe you'd like an update on this one. Called my local bearing place, Applied Industrial Technologies, and they in fact stock a 20/42 bearing. It's ABEC1 (electric motor quality) sealed. Ain't cheap, but it would make this damn-near a bolt-on deal. 23 bucks per bearing. I'm debating which way to do this now, but it's an interesting bit of information.