That bear spray will work on "Yogi and Boo-Boo" when they are nosing around the trash can and you want to run them off.
However, If you have a sow charging you, black or brown, because you got between her and her cubs you will wish you had that .357 or a 10MM when she hits you in the chest running you over like a freight train.
That bear spray is a money maker for the sporting goods shops, its something for the tourists, hiker and "Turtles" (aka backpackers) who visit BC and Alaska to make them sleep better.
If you surprise, wound, or are in the wrong place at the wrong time the ONLY repeat ONLY thing that will improve your odds of getting mauled is a gun.
I guided in GMU8 (Kodiak, Afognak, Raspberry Islands) and lived/hunted in GMU6 (Cordova) for 14 years. I have a little experience with these animals. FWIW, moose kill more people every year than bears.
As suggested earlier, a shotgun is fine protection, but a rifle is better. A pistol is better than a rock but you better know how to shoot it under stressful situations. Solid penetrating bullets are necessary to get into vitals. Hard cast or premium bonded projectiles preferable over all else. me I like the hard cast stuff, Jae Bok Young, he makes these, none finer. Here is a 250GR hard cast boolit for .45LC, shot out of a Ruger Bisley revolver using a heavy charge of your preferred powder would be a good choice if a pistol is all you could get your hands on.
I just sold a .45-70 Marlin Guide Gun on here that I had built for just this type situation, backing up clients who have wounded something that needs killing.
Here is a photo of it;
A handgun will simply make you feel "Better", I don't think much of them for killing bears. Might be alright for poking one in the ear with the hammer back to make sure its really dead...Like they say, "A 9MM may expand, but , a .45 will never shrink"
Gee whiz! That sure is a big gun! Why do you carry a .45? Because they don't make a .46
Have fun!
Jerry