Another 5x7 sale for $229 back in April
https://rmyauctions.com/bids/bidplace?itemid=53936
From the description:
"The offered photograph has some age to it and from our analysis it appears to be a 1960's or possibly 1970's example of a photo that would otherwise break $50,000"
So now we've seen well educated guesses from solid sources on different 5x7 examples possibly being from the 1950s, 1960s, 1970s, and/or 1980s with a photo expert thinking the discussed example might be pre WWII. Paul also has a larger format he suspects is circa 1930s or 1940s. This image very well might have been trickled out through the years. Hopefully this one is the oldest, come on 1920s!