I wonder how it would work if the one of the solid pins on the rear of the handle were removed, the hole enlarged just a tad, and it was replaced with a tube/hollow rivet with peened/rolled ends?
Another option could be to drill a hole in the rear of one of the brass bolsters lengthwise (never having to penetrate the knife from side to side), thread it, and put in a stainless screw, head facing the rear of the knife so that it did not interfere with the grip of the knife. The head of the screw, could have a hole drilled in it for a stainless steel split ring, much like a Victorinox Swiss Army Knife.
Too bad they no longer make the Buck 110 with titanium handles as this. IMHO, the optimum Buck 110 would be one with the old titanium handles or a simliar adonized alloy handle with a S30V blade, provision for a lanyard, and maybe with something to assist one handed opening.