I'd not run across one of these before. 18.1 mm in diameter, 2.6 mm thick. Reverse is offset 90° from the obverse. Seemingly designed so as to give the impression it was derived from an actual coin, although this is clearly not the case. Thus, I have no confidence in the validity of that date, and wouldn't be surprised if it was in fact from the 1950's, 60's, or even 70's.

