I have to say when I first bought the one from Unique, it reminded me of a shell casing, and I wondered if that's part of what he'd used, as they would have been readily available, and a cheap (literally throw away) source of brass.
As for the bullet with your name on it, that's just great! An image of Baldrick leaps to my mind, but putting that aside (with a wry smile), nice idea. Easy to lose it from the hank, and to remove it from the tube, with it "ready" for it to re-appear there.
Maybe I'm a bit thick though

Sticker shock? Are you referring to the price, and Niffen tube? Happy to show my ignorence, what's a Niffen tube?
Oh, and that's one hell of a modification!