made circa 1888-1911 you can't prove it a antique but they also can't prove that it's not
the other thing The .41 rimfire round supposedly produced a muzzle velocity of 425 feet per second. Many years ago, a muzzle velocity below 500 feet per second was not considered a firearm in Canada but I'm not sure if that still applies
I know you can't get a antique letter from the RCMP for a derringer unless it's a older 2 line address