A quick double check of mine, on a Western Flyer space frame rat, is RB2, brake arm says Bendix and USA; so from your comments I have good one!
The coaster brake is mighty weak, so I guess I will have to dig into it and see whats up. From what Ive read here so far it will be pretty easy for an old motorcycle mechanic to mess with.
I havent found any numbers on the frame yet to narrow down the production year, but I think it is all original (that is, it doesnt seem to be a bitsa).
Thanx for the info!