I will assume, ignoring previous comments, that you mean to ask about the legalities of smoked and non-smoked receivers.
If I've missed your sarcasm or something, tell me; I'm not too good with this 'Interwebs Sarcasms' that you speak of.
Basically, the receiver's colour has no impact on legalities on owning a gun here and now.
Transparency is one of the regulations stated by the CBSA and by importation legislation that allows free importation of guns (Well, free-er, not completely unregulated) into Canada, because of the fact that no modern firearm has a clear receiver, nor do they want to.
Inherently, then, for the realism of the sport of Airsoft, you want a full-black receiver, or something that looks politically and realistically accurate. As long as you don't try to get these said full black receivers from other, Foreign countries, you are fine with owning them here in Canada. OWNING. NOT IMPORTING. VEEEERY IMPORTANT.
Please please PLEASE do NOT import full-black guns, or, for that matter, ANY guns from America or ANYWHERE THAT IS NOT CANADA.
Owning full-black, no problem. Importing, not so much.
Again, if I missed some portion of an inside joke or sarcasm/humour/otherweirdthingthatyou'regoingtolaughatmefor, please feel free to laugh at me for a period of time.
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