Where I live, cleavers are like cast iron cookware--it's not something you go to a store and buy, it's just something you inherit. I marvel at the talk of Chinatowns, Chinese grocery stores, and metropolitan stuff. It would be so nice to have such things. Around here, there's only one place I can really remember ever seeing real cleavers in any numbers, and that's flea markets. A couple generations ago, virtually every household here would have had a serious line-up of butchery tools, most often including cleavers. Cleavers of all shapes and manner of condition can be found, from gently used kitchen cleavers to well-abused two-handed monsters. If a person is willing to do some cleaning and often some work to the the handle, a bargain can often be had. One thing about older cleavers is they were all built to be used, and used hard.
When I was a kid, I always marveled at the huge cleaver hanging up in the pantry at my grandparent's house. I helped quite a bit, but we usually used a hatchet for heavy chopping rather than the cleaver. We still have that cleaver and hatchet, but I don't typically use them. The largest thing I butcher is deer, which would unlikely ever exceed 200lbs. There isn't really much purpose for a cleaver on an animal that small. A slightly large knife can hack through anything on a deer this size. I've found cutting through bones often is not something I want to do, anyway. Bones often in their natural state do not cause problems, but when when we cut them up is when we have issues, like the splinters mentioned earlier. A good example is asian carp. About 99% of people here think you can't eat them because "they are full of tiny little bones." No, the bones to which they are referring are about 3-5 inches long. If you accidentally swallow that, you have issues. What happens is people will take a fillet and just randomly cut it all willy-nilly. Now those bones may be any size. I think there are also some diseases that can affect bone marrow and nerves that can taint meat if cut during processing, but I'm a bit fuzzy on that.