Apparently there were differences in the frames as they evolved over time, which does help date them to a period. Mine was dated to the 50s. I was told they started over every year with the serial numbers, which makes them useless for dating. Mine is I912 for what its worth. Like the one on ebay it also has no headbadge, or holes for one. Jeff Groman seems to be the expert in such matters.

I find it interesting that the Waterford paint job (though beautiful) on Scooper's is much fancier (even given the modern materials) than the originals.