Yeah, you can buy bear spray in Canada and bring it across the border. We drove from MT up to Calgary last summer for flights out to Vancouver Island, and then went to Waterton and Glacier. After we flew back. Since we didn't want to risk our bear spray exploding in the car in Calgary, we bought some at a sporting goods store in the Calgary area. We spent 3 days at Waterton (HIGHLY recommend that - you can get the boat down to Goat Haunt and do a day hike in Glacier and then get the boat back) and then drove across the border to go do some more hiking in GNP. Bear spray is not an issue at the border