Signalling devices are not considered firearms when entering Canada. We went down this path a few months back.
"Devices designed exclusively for signalling purposes (e.g., flare guns), and intended to be used solely for that purpose, are exempt from the requirements set out below. However, some flare guns that are based on the same frame or receiver as a firearm are considered to be firearms and are not exempt from firearms controls."
Thanks That helps alot. I have transported rifles up to Alaska through Canada and it was pretty painless. Easier if you stop at US customs first, fill out the form, have it signed by customs then to the candian side.