It’s from the 1950’s (I just ran out of room in the title).

It’s also a 6x9 but that wasn’t an option in the eBay size guide (probably because it’s not common anymore)

It’s also supposed A POSTCARD but eBay doesn’t have: Sports Mem, Cards & Fan Shop > Vintage Sports Memorabilia > Postcards⁠ as a category. (Only Photos is a category)