Doing a little more research, this catalog is 1955 so mid '50s is a good assumption.
Thanks, GF, I was lucky to get this one. Was heading up to Michigan for Labor Day weekend and I found it on Craigslist. Back when Craigslist was a thing.
Made arrangements to take a look at it when I got there and nabbed it for $275. A little more than I wanted to pay, but I knew these weren't easy to come across, especially in this shape, so I happily paid it. Best thing is it had been at a shop in Pontiac it's whole life, not far from where I lived growing up.