2 handguns
Am I right in understanding the OP intends to carry 2 handguns, one for bear/cat and another for human?
That means two of everything....spare ammo, mags, holster rigs, way too much stuff for me to carry very far if I'm toting some type of daypack with hiking stuff in it too. I'd just as soon carry some type of carbine, as two handguns.
I'd leave the 9mm at home, limit the SA revolver to the 4-5/8" variety for portability sake, and n .357, load it with some type of 158 gr or up SP or SWC load that is the equivalent of factoy velocities, and be done with it.
The G20 is a viable alternative to the large frame .357's...but slightly off post.