No response? Obviously we have no interest at all in RCAF gear!
No sorry, I lie!
What is it you would like to know? You have already found the nomenclature of your flare pistol. The 1 1/2" flares were used in RCAF (and RAF, RAAF, etc..) aircraft as signalling devices. The socket bayonet style fittings around the barrel were locked into ports in the Aircraft's fuselage to fire outside. When fitted to the port, the pistol could still be opened an loaded in place.
Quite sensible really, in a Bomber with several thousand pounds of bombs, hundreds of gallons of Avgas, thousands of rounds of MG ammo, several of your crewmates, buffeted by turbulence and Flak, and the stress of signalling to the other aircraft when to commence the bombing run, which means the difference between hitting a ball bearing factory or marshalling yards, or missing and hitting a residential suburb, the consequences of an Accidental Discharge on board could be quite high.
Poor wee ground troops used hand held 1" flare pistols, with a design unchanged since WW1.
The US had a similar version that fitted the same port and fired the same sized flare, known as the M2, that was a bit cruder in design, but much quicker and cheaper to produce.
PS If you are not intending to sell this, perhaps a Moderator could move this thread to WW2 Equipment Forum?