Wow. I guess it was "you show up, you are in". Those Canadians are merciless...
I checked out the Wikipedia page for the tournament. Looks like there were no qualifying or lower divisions back then, and Canada was represented by the Sudbury Wolves (which isn't the first time I recall reading about the Canadian "national" team being represented by an existing club team instead of a roster consisting of players selected from various clubs).
If I recall there was some Olympic tournament early on where two club teams claiming to represent "Canada" showed up. I forgot what happened after that.