Beautiful Weyersberg Wolfgang!
It is around the 500 mark that it was thought the numbering stopped. 540 is the highesst I am aware of. All the later numbered pieces I have seen thus far had the MM higher so this one is an interesting piece. Why the mis-match? How can we begin to speculate? Maybe the engraver made a mistake and they had to procure another x guard. We`ll never know but it doesn`t really matter. Very nice piece you have and congratulations on a rare find.

War is when your government tells you who the enemy is.
Revolution is when you figure it out for yourself.