Hunter Baltimore Rye Whiskey Puzzle

I think the pictures say more than I can.  

The envelope is 4-1/4 inces long and 2-1/2 inches high.  The horse cards are 2-1/2 x 1-1/2.  The rider card is 3-1/2 x 3/4.  I have found a little info about the Hunter Baltimore Rye online, but I can't find anything about this item.  I'm guessing it was for advertising purposes.  I would be interested in it's value and possibly selling it, but would really like to know more about it first.