I have a 72t I am pulling to swap to a smaller 60t that is original Bonanza. I think the kit500/BC1000 bikes normally got the 72t sprockets. Nothing wrong with it and its nice with good teeth, just have a compete setup for 60t ready for it if I decide to finish it.
This is it, still on the bike today. this is for the sprocket/drum only NOT the brake assembly. $50 + whatever priority mail postage is currently (think it around $8 now)