1970s Parker Brothers Pro Draft Football Game

[BradH]

I picked up this 1970s football game at a yard sale recently and didn't look closely at it until now. The box is in pretty good shape, except for some crease marks in the top right corner (as if something heavy was placed on it or someone stepped on it). The inside contents are very clean and it appears to have hardly been played, except for the Topps football cards, which have some slight corner wear and a few creases here and there.

The box says the game contains 50 trading cards, but I counted 52 in the stack. When I bought it I didn't search it closely, but some "star" cards - Staubach, Simpson, Harris, etc. - were mixed in throughout the stack.

The Topps cards vary over several years in the early/mid '70s. I understand that the kid who owned it might have mixed in his own cards, but I'm wondering if a specific year of Topps cards were used originally or were they actually mixed among several years when the game was distributed?

Anyone here know much about this game? Thanks.