That’s weird, because the Krieghoffwebsite shows that they do have pierced and highly engraved top levers available in their custom range.
Bruno at Lombardo‘s sporting has a full selection on his website of custom engraved parts for Krieghoff, of course, if you Google custom pierced top lover, any number of artisans that make them show up
I would just call a Krieghoff sporting arms customizer and tell him what you want.
One quote I saw was $850 for the engraving
It’s not something I’m actually interested in, but it sure was easy to Google up more people than I could call in a day and a half.