George was brother to both Thomas and Alexander and he also made bagpipes, although few examples have surfaced up to this point in time. No doubt other sets exist however the challenge may be in finding them!
The bagpipe below is a probable set of George Glen bagpipes. I spent a great deal of time with this bagpipe and had the privilege to restore it.  Many of the profiles and details line up however no maker's stamp could be found. It was a very good playing bagpipe and perhaps a bit more robust sounding than other instruments from the Glen family of makers. 
The owner of these pipes, Mr. Chris Brand, was kind enough to provide me with these words.

"My father, Marvin S. Brand (1917  1976) was in World War II, Pacific Theater, U.S. Army Air Corps 5th Bomber Command (the 5 U.S. Army Air Corps, later to become the U.S. Air Force). He was stationed in New Guinea in 194344 (Port Moresby) as a Tech Sergeant. During this time he was "detailed" to an outfit of the Australian Air Force. He made acquaintance with Sir George Bell of Australia, a member of the Australian Parliament. Sir George had these pipes that he said he had played for many years, including the Boer War. He did not specify his regiment that I know of. He had been wounded in battle and was unable to play the pipes anymore. It is not clear whether my dad paid for them, and if so, how much. He told my dad that they were "Glens." Sir George Bell died in 1944.

George B. Gray was former Pipe Major of the Queen's Own Cameron Highlanders and later with the Edinburgh City Police Pipe Band in 1950. His opinion was that these pipes were Glens.

My father played these pipes until his death in 1976. After than, they became mine and I have played them as my primary bagpipe since then."
George Glen