Here is the flyer portion
https://www.ebay.com/itm/165083459718
Nintendo Power Source was a website on the AOL network. The item has a part number (R00857) which leads me to believe that this was included in something. It was not in the Nintendo Power issues 84 (Ken Griffey Winning Run cover) or 85 (contest) or at least the ones on Ebay. It could have been included in a bagged newstand issue or included with a game. It is from 1996 but beyond that I can't find where it comes from.
TCDB Collection Leaderboard spots:
#1 Alexei Zhamnov #1 Shane Doan #1 Phoenix Coyotes #1 Arizona Coyotes