Bluebonnet has been reproduced for an RR museum in or near Dallas. I don't know the details, but beware, and check for a vintage backstamp.
More items have just recently popped up showing Niagara, Oneida and Buffalo backstamps. These are all very modern counterfeits. There is nothing on them to warn the unsuspecting - and of course, unscrupulous dealers aren't helping. Stick to the known vintage backstamps! Any Buffalo backstamp depicting a buffalo (the animal) is a modern reproduction.