I picked up a pair of "vintage" Florsheim Imperial longwings in burgundy shell cordovan off of eBay last week. I love the shoes, but I'm curious how old they are. I've done a little searching, but I can't find anything of use. The soles appear to be original, and they're in (I think) very good condition, so it doesn't seem like they're *that* old. Does anyone know how to tell?