First off - I lived in Delta for a few years at the base of the Grand Mesa - exquisitely beautiful country and I love the Grand Mesa and the Uncompahgre plateau.
Second: Of course there is always something bigger and better, but your .357 is fine. We do hand-to-paw combat with big black bears (up to 600+ pounds) up here and often wade into the hound and bear scrum (the big ones don't tree)to kill the bear with a handgun. .357 works just fine - we use CorBon 180gr BCSP (bonded core soft point) that achieves 1200+ fps out of a 4" revolver barrel.
There is no handgun in the world that is good medicine for a charging, lathered up bear. That's why they make 12 gauge shotguns, 45-70's, .450 Marlins, etc.