In Canada pepper spray is marketed as "bear spray" and can be bought almost anywhere by anyone. Here's the wiki section on pepper spray in Canada. I imagine it's quite easy to get in the states, especially any state that contains lots of "wilderness".
From Wiki: "In Canada all products with a label containing the words pepper spray, mace, etc., or otherwise originally produced for use on humans are classified as a prohibited weapon. Only law enforcement officers may legally carry or possess pepper spray. Any similar canister with the labels reading "dog spray" and/or "bear spray" is regulated under the Pest Control Products Act - while legal to be carried by anyone, it is against the law if its use causes 'a risk of imminent death or serious bodily harm to another person' or harming the environment and carries a penalty up to a fine of $500,000 and jail time of maximum 3 years."
Wow, I knew you guys weren't allowed to have guns, but pepper spray? That's crazy! Pretty much every girl 16 or older in the U.S. has a can of pepper spray in her purse or on her keychain.
In regard to pepper spray on a bear, that reminds me of a forest service anouncement I saw a while back:
"The Forest Service has issued a BEAR WARNING in the national forests for this summer. They're urging everyone to protect themselves by wearing bells and carrying pepper spray.
Campers should be alert for signs of fresh bear activity, and they should be able to tell the difference between Black Bear dung and Grizzy Bear dung.
Black Bear dung is small and round containing nuts and berries, and sometimes squirrel fur, while Grizzly Bear dung often has bells in it and smells like pepper."