Not a Barling.
The "Trombone" was made, appropriately enough, by the Trombone Pipe Company, Limited, located in London at 87 Wool Exchange. The Trombone was an early attempt to screw around with the internals of a pipe in order to make the smoke cooler and dryer, all while reducing nicotine and making the pipe easier to clean. It also made your bed, watered your horse, and chastised indolent servants.
The first mention I can find of the company is in early 1895; advertisements (like the one below) continued into 1896, but thereafter I can't find the company in London directories, newspapers, or almost anywhere else. The answer lies in a June 17, 1898 listing in the London Gazette stating that the company had been struck off the register and dissolved. So after a brief splash the Trombone Pipe Company was no more. Apparently they were ahead of their time, lousy marketers, or made a poor product. Your friend's pipe looks pretty cool, so I'm guessing it was one of the first two.
Curiously enough the Trombone appeared in trade brand directories until 1934; was the company reconstituted in some fashion and the pipe really made that far into the 20th century? Or was that inertia on the part of the people putting together the brand lists? No idea, although I will say I find it suspicious that no other mentions of the company can be found (at least by me).
Incidentally, note that the lozenge around the EB is an oval in the ad and an elongated diamond on the pipe. That could mean something, or then again it may not. You'd need to know the maker to really figure it our. Likewise it would be useful if the hallmarks could be read well enough to determine a date of manufacture for the band.
One final clue: the intellectual property number associated with the pipe is 183,097. I haven't looked into it, and so can't tell you if that represents a trademark, patent, or design registration.
