T5 Pinkerton mystery cards

[Bicem]

I recently picked up this Home Run Baker card and was wondering if anyone had any insight into exactly what it is.




It’s not an unmounted T5 as it’s printed on thick cardboard stock (vs thin photo) and notice the wide borders (vs the skinny ones that T5’s have, shown below).




It’s also not a Pinkerton w530 since it’s a real-photo card and not a printed one.

The Baker card was actually used as a postcard by someone (although blank backed) and was mailed on 10/30/1911. I can post a scan if needed but it just says something along the lines of congrats on the Phily win (The A's completed their World Series victory a few days prior on Oct 26th).

I have also recently seen one other very similar card of Topsy Hartsell…


(posted with owner's permission)


So, anyone have any ideas? Some sort of new uncataloged Pinkerton issue? Or a production photo on cardboard stock that was used to create T5’s perhaps? Measures 3 5/8” x 6”. Thanks!