Made these for a Powerman 5000 show a few years ago. I threw them out into the crowd as goodies from one fan to another. Had actually brought a silver sharpie with hopes of getting an autograph but that fell through.
Print the model with two colors preferably, then, mix some epoxy (I used Loctite), and spread a layer of glue onto the surface of the base to seal.
The author hasn't provided the model origin yet.