when i think about heading West deep into a Mountain refuge, I always get concerned about several things.

It's harsh climate in unpopulated areas.
The perilous risk of avalanches.
And unless there is total breakdown in civil order, the need to posess and utilize legal firearms for hunting and protection from wild beasts. Which requires a permit and hunting licence, and then you still have to hunt in season as per the rules, not to mention bag limits.
The same goes for fish. You just can't run amok and hope to get away with shit like that perpetually while society still continues.
Unless you have located some isolated shangrala untouched and unclaimed, and I don't even think you can squat on crown land which if im not mistaken has rules about habitation and time limits for camping.

heres a simple example i found first hit from goog search
sorry it has neetflicks pop up add
[link to www.nowpublic.com]

so your looking at purchasing a land parcel that is large enough to be sustainable for subsistance and also a dwelling or construct one.

And you better work out a diet and how to maintain vital nutrients in advance. And your sitll going to need consumer products or face imminent unnecessary shortening of your lifespan.
Not to mention that you will need to know skinning and tanning when your clothes and boots wear out, unless you plan on running around in a grass skirt.