This is a picture from my family's book & stationery store that was in Aspen, Colorado, and I'd love to get a better idea when it was taken.
We owned the store between maybe 1905 and maybe 1945. The calendar on the wall looks like it says July, with the 1st on a Sunday, which means it's either 1906, 1917, 1923, 1934, or 1945. I've been trying to decipher the names on the magazines and compare against online images of covers from those times but haven't had any success. The comic book (?) on the table (lower shelf, right side) looks like it's got a biplane on it, and with the "Victory" poster on the back wall (right side) that would suggest 1917.
In case the picture doesn't get uploaded at its full resolution, the "original" is here.
I realize I did leave out one rather important piece of information. That's my grandfather and he was born in 1883.