When I was importing Darne guns, I was put on notice where the mark would be, what size it would be, what information the marking would contain, and that failure to so mark said guns was a crime. It was to be on the top of the barrels.
There was no discreet option. The Customs people at port of Minneapolis also inspected the gun for BATF markings. And, collected the excise tax on said guns.
Port of Minneapolis is an unfriendly place to import firearms to. Trust me on that.
Unless the law has changed, the stuff has to be engraved or stamped on top of the tubes.
I had two guns sneak through without it. I wish none of them had been marked, but,
it wasn't my call.
Best,
Ted
