[JLange]

I see the connection now with the SH prefix # on the cards. These are cataloged in the newest Standard Catalog of Vintage Baseball Cards, pg 384-385. The description says cards numbered to 115 have portraits in an oval frame. Your George Kell and Pepper Martin look nothing like this Bob Feller, but they are apparently from the same set. There was also a Sport Hobbyist set of Team Composites from the same year, also with SH prefix #'s.