Snowdog, you say your friends uncle was an officer. Many commonwealth officers bought and carried their own pistols and ammunition in those days. Not sure of my facts, but it wasn't frowned upon and supposedly quite common with well heeled officers. Many were gifts as well from friends and family.
Mauser broomhandle pistols were favored by many for obvious reasons and much more comforting than a swagger stick and a whistle.
I had one that looked exactly like that one about 30 years ago and was talked out of it for $1500. It paid for the wireing in my house. It was bought and carried by a British officer dureing WW1 and later used in a crime spree and as a hunting arm for close range shooting on a trap line.
Beautiful pistol and rig by the way, thanks for showing it to us and for bringing back memories of one I let get away.
bearhunter