I have one of the Primer Pistols and it's been a good tool. The film canisters clean up easily; after shooting epoxy primer I refill the canister with solvent and spray it out to clean the pickup tube. Wipe the canister out and it's ready to go again.
I also have a larger spray gun that uses the same principle on a larger scale: pint Mason jars for the product. It's called a Critter and is made in Canada. Available from a number of sources; I bought mine from Lee Valley Tools; they also carry spare parts, jar gaskets, etc. see
www.leevalley.com
The Critter is my gun of choice for shooting Akzo primer. Use a canning funnel in the Mason jar to keep the mixing mess to a minimum. Put in the two parts of epoxy, slap the Mason jar lid on and shake to mix; let sit for the induction time, then swap the Mason lid for the spray gun and shoot. Run some solvent through the pickup tube for cleanup. Spare jars available from the grocery store.
Good luck,
Mike