I had seen that auction too and wondered who would spend that much on a mold! I was told the original mold was destroyed but looks like it went home with someone instead. It has all the tells of the original pulls so its safe to say you got a winner.
Here is another original from that mold in private hands that not many have seen. The masks are either very well planned out or were a total stroke of luck as a simple change in lighting or a slight angle and it goes from silly to sinister.