I posted in the ISO thread, but since doing some research I have become even more baffled than before, so I'm starting a thread. I have an awesome single speed coaster brake project in mind for a bike frame that I've had sitting around for about two years, but unfortunately it needs a Thompson bottom bracket.

Do they only come as a cottered crank? This isn't a deal breaker, but I was planning using a square taper.

Is there anywhere to buy them or any alternative? There are a couple on eBay, but I'd rather see what else is out there before I bid on one.

Why were they used, why did they stop being used, and what was the quality like? The bike this is going on isn't high performance or anything like that, but was it a sign of the lowest of the low?

Thanks,
DE