I really don't have an opinion on the authenticity of the photos. However, the frame is from my father's home town. As a child I remember speaking to my great aunt Rose who lived there about baseball. She was in her mid 70s at the time. She was an avid Pirates fan but never saw them play in person. I asked her if she felt bad about missing out on seeing Clemente in person. She said, "No I saw Josh Gibson." I had no idea who he was. She told me that as a young woman she would travel to neighboring Masury Ohio to watch Games and saw him play there. Her stories were my introduction to the Negro Leagues. She died 20 years ago and took those stories with her. I wish I had recorded her but lacked the foresight at such a young age. She was obviously very progressive and quite a story teller.
Sharon is a small economically depressed town. I have returned there to visit an aunt who lives minutes from the address on that mat. While there I have stumbled upon a Sovereign back Brooklyn Dahlen, a blue version T206 Evers, a beautiful Beckley, and a Variety of vintage Indians items in small nondescript shops. Ironically when I was there last I stopped at a local antique mall and they were auctioning off a panoramic photo of the Homestead Grays. The auction was scheduled for a date after I was to return to Washington. They didn't look to be original despite the auction house guarantee. Had I been there I would have considered bidding simply because my aunt Rose and the way she beamed when telling me those stories. I called my father who is now the same age as aunt Rose when I last spoke to her. I asked him if he recalled the name of the photographer on the mat he said he had no such recollection. But he laughed about the stir Rose must have caused with her family by going to those games.
I found another mat with the same markings on ebay so I doubt it would be terribly hard to remove the original photo contained in this or any other vintage mat and replace it with another photo.
http://www.ebay.com/itm/antique-cabi...ht_1490wt_1091