I too have quite a few of these photos.
Adam may be correct on who produced them. But Manny's did sell them. At least some of them by the Manny's Catalog shown below.
At the top of the page is shown a Williams and a Mantle/Maris.
Under the Williams they list the individual players for sale from the 10 player team sets we are familiar with as Manny's. But the Williams photo does not go with this list, but rather the photos listed at the bottom of the page under the HOF Bust.
They are called ALL STARS OLD TIMER PHOTOS. This is a partial list and while your Fox and Mathews are not listed here does not mean they are not part of the set.
Did you win these on ebay from Estate-Finders?
https://www.ebay.com/itm/25598884869...p2047675.l2557
If so they were my consignments and I had expected the photos to be listed individually so player collectors could get the ones they wanted. But he listed them as a group, which I think cost me money.
Here is the Manny's catalog page: