I went a totally different route. I carry my hunting handguns in a Boyt Contender case. Add D's to the handles (Total of 4). Then I add a removable strap, and carry the pistol cased like a Muzzleloader Possibles Bag, "Cross Chest". If stalking unzip the case a little so that you can draw out of the end.
When I get to my ladder stand I attach the case to my 550 Cord Gear Rope and pull it up along with my gear bag.
Simple, reasonably inexpensive, and it works well for me.
Bob