Canadian tax stamp help

[lenguamor]

Anyone familiar with Canadian tax stamps? I'm trying to date these La Palinas; from the model on the box I know they're post-late '60s, maybe '70s...maybe later.

http://i129.photobucket.com/albums/p225/dirtyrottenbastard27/IMG_2296.jpg

http://i129.photobucket.com/albums/p225/dirtyrottenbastard27/IMG_2295.jpg

http://i129.photobucket.com/albums/p225/dirtyrottenbastard27/IMG_2294.jpg

Any help would be appreciated.