That is not the same die number. He means Wexler's 1960-D WRPM-018. (The split serif on top is nothing like the coppercoins one.
The Wexler 018 Is too far south and there is a lower rotated mark on it. I don't see a match in John's files for this die yet. I find this one interesting because of the lower serif that follows up to the corner then turns east. But so far nothing like that.