FWIW, stone crabs are caught in parts of the Gulf and Atlantic other than the Florida coast, and they also come up from South America. And they freeze pretty well, like most crab.
But nothing compares to the fresh stuff harvested in South Florida, which only happens in season and is pretty strictly managed.
Joe's in Chicago has stone crab all the time. It only has fresh Florida claws in season, though. They'll tell you if you ask and sometimes they volunteer it.
I think the original Bob Chinn's more closely approximates the Florida seafood experience, for better or worse, though Joe's is very good especially for steaks and the fried grouper sandwich.