I would find a Pilot that's flown the rought before fly up with him.
What time the year you plan to do this?
Where you flying from?
Where you going to? passes and mountains villages where 100LL is available
What rateings you have?
What Type of plane and its range?
A firearm isant really needed, you will be dealing with Canadians for some reason the authorities there have a dim view of hand guns and semiautomatic anything!
If you have to put down somewhere chances are you will be lucky to get out the plane at all with what's on your back, you may have broken legs mabe knocked out upside down and hypothermic succombing to the elements is primary concern, having a operable hand held with extra batteries and the new ELT (they changed the frequency they monitor) with fresh batteries (have your A&P or IA check ELT) when brushing off snow the ELT antenne can be easily broken off, may have to live with whats in your pockets (fishing vest comes to mind with stuff in all the pockets) flight plans very important, not pushing the weather is another (we can alway's come out when the weather is nice and look for you) I have a few pilot friends that racked up some time in these parts I'd glad to get you in touch with the Fellas that flew up here and have survived a crash or two.
Right off I know three guy's that would be good sources
I rememberd another so its allready up to 4!