Pistol ring (l), hand cannon (m) and lighter gun (r)
Club Littlegun has a fantastic collection of unusual weapons, including some unusual gun/knife combos! http://www.littlegun.be/curios%20et%20antiquites/a%20a%20images%20curios%20et%20antiquites%20gb.htm - Thanks Emperor!
I have been searching the internet to see if there is a write up about it but no luck.
Thank you.
Kenneth Yerty
Ocala, Florida