Having spent quite a bit of time with a 10mm Colt when they first came out, I would have to STRONGLY recommend against betting your life on that round when it comes to bear. Granted, the only bear I know about are black bear, but even those would leave me nervous with a 10mm.
The trade off is to carry what you can shoot. Shoot under the conditions which may be present when you need it most. Try a stress/shooting test and see how it goes. I know for myself, and from what I learned from years of training people to survive an armed encounter, when the defecation strikes the rotary oscillator, accuracy tends to fall off a bit.
Pepper spray is a good option. It works on bear most of the time.( Works on me 100% of the time.)
If a 10mm is what you decide to use, please consider, for your well being, something other than a Glock. I carried Glocks for years, and repaired a great many for those I worked with. You won't find a Glock in my house.
If you intend to hunt with a partner, you should be able to get by with a 25acp. Just knee cap him, and run.