Ronald Reagan Convention Medallion

Submitted by Larry:
I recently came into possession of a bronze commemorative medallion from the 1980 GOP Convention in Detroit Michigan sponsored by Cadillac depicting the renaissance center on one side and an Oak Tree from the First GOP Convention 1854 Jackson Michigan on the other. It came in a Blue bag with Gold draw string and a slip of paper stating "Cadillac welcomes you to Detroit Michigan USA". I am not interested in getting rid of it but I cannot find anything anywhere giving any idea of its value. I want to make sure that it is properly insured and valued. Any states on how many were made and distributed would be helpful as well. This was as we all know the convention Ronald Wilson Reagan was Nominated.