It's the small cans of spray, the ones you can easily conceal, that will get you into trouble at the border. If you have a big can that is clearly labelled "BEAR" spray, then there will likely be no problem. However, if it is a small can labelled for personal protection, then you may have to hand it over at the border.
We don't carry bear spray anywhere here. That stuff can harm the humans using it if the wind is blowing wrong. The bear needs to get too close for it to be effective too. Instead, we have "bear bangers" here at the cabin. When ejected towards the bear, these tend so scoot them off in the other direction. Smaller to carry too. Although, banging pots & pans while screaming like a crazy lady also works well, and I'm speaking from experience. :B