It seems that back in late 2016 an individual seller made their own Cubs set. They used the American Caramel set from 1909 as their inspiration and came up with this unlicensed set.
Whoever made this did a pretty decent job. The design is fairly close. They also used normal thickness card stock so the cards aren't flimsy. The cards seemed to be cut professionally too, as they are all uniform in size.
The set has 21 cards, one for Joe Maddon and 20 players. All of the most important players were included.
The set makes a nice little keepsake from that awesome season.