here is a semi decent page about it
ehow.com/list_6802569_canada_s-silencer-laws.html
or you can look at the criminal code
laws.justice.gc.ca/eng/C-46/FullText.html
but basically section 92.2 says:
(2) Subject to subsection (4), every person commits an offence who possesses a prohibited weapon, a restricted weapon, a prohibited device, other than a replica firearm, or any prohibited ammunition knowing that the person is not the holder of a licence under which the person may possess it.
subsection 4
(4) Subsections (1) and (2) do not apply to
(a) a person who possesses a firearm, a prohibited weapon, a restricted weapon, a prohibited device or any prohibited ammunition while the person is under the direct and immediate supervision of a person who may lawfully possess it, for the purpose of using it in a manner in which the supervising person may lawfully use it; or
(b) a person who comes into possession of a firearm, a prohibited weapon, a restricted weapon, a prohibited device or any prohibited ammunition by the operation of law and who, within a reasonable period after acquiring possession of it,
(i) lawfully disposes of it, or
(ii) obtains a licence under which the person may possess it and, in the case of a firearm, a registration certificate for the firearm.
"prohibited device” is under section 84 and means
(a) any component or part of a weapon, or any accessory for use with a weapon, that is prescribed to be a prohibited device,
(b) a handgun barrel that is equal to or less than 105 mm in length, but does not include any such handgun barrel that is prescribed, where the handgun barrel is for use in international sporting competitions governed by the rules of the International Shooting Union,
(c) a device or contrivance designed or intended to muffle or stop the sound or report of a firearm,
(d) a cartridge magazine that is prescribed to be a prohibited device, or
(e) a replica firearm;
so you can own it if its on a replica firearm or not intended to muffle or stop the sound of a firearm.
anyways, im no lawyer but thats what Im goin with. I know you can get them for paintball guns and ive seen some forum posts talking about people who have them that seem to imply that you can have a mock can supressor but you want it to be as light as possible. As far as importing goes that starts at section 103 and I got bored before getting that far but Id guess if it didnt count as a prohibited device you can import it.
If you get dinged with a prohibited device its jail for a period of less than 10 years and importing one is jail for a period of less than 5. Dont know that Id really want to gamble on it myself.