As mentioned, you cannot bring an airsoft gun into canada. This is because of Canadian Border Security Agency policy regarding imitation and replica firearms. There is no way around it -don't ask.
As for playing at 16:
Due to the nanny-state Canadian gun laws, and the potential legal ramifications of minors with imitation firearms, most game hosts require players to be 18+.
That's not to say you won't have a way to play. Depending on where you are going in Canada (more info would be helpful), if you have a parent or guardian willing to come to the field with you, and the game hosts, you might be able to play.
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