First of all, I am not an expert in the field of bank collectables, but since I see lots of junk out there, here is my spin based on what my father told me years ago:

I have an original black, Uncle Sam 3 coin bank that my father had as a kid.  If you are looking for one of these that is original, I would suggest the following:  The only color my father EVER saw was black.  There was never a plastic knob on the pull-down lever.  Originals have a lever with an open ring with about 5/8" OD and a 3/8" ID (more or less). Originals never had a label below the coin slot.  Also, there was no hole in the rear for bills; the original hole was in the bottom.  The sides had gold scroll work, which is probably faint on most examples.  Remember, if it looks too clean after sitting for 50 years, it's probably a modern fake or copy (and there seem to be a lot of them out there! Expect some rust!