MYSTERY MINI #1

These are 3.4" in diameter with a wide flat top, steep shoulders, and thick rim.  They were made around the late 1970s to the mid 1980s. The maker of these Minis remains a mystery, therefore the name Mystery Mini.

And now the mystery grows with the green basketball championship Mini dated 1997. From the top, it looks identical to the other Mystery Minis, but turning it over reveals a thinner lip. Was this mold retooled for another run 10 years after they stopped producing the other Minis?