While I totally understand what you're saying, two things to consider- depending on what part of Alaska we're talking, not having a tall truck with 4x4 might not even be an option (most of the state is backwoods AF, dude might be off grid for all we know), and FWIW Subarus aren't cheap (even for old beaters for some reason they hold their value really well) and they get **** gas mileage as well. I have owned several and only ever got over 20mpg on super long highway trips on mostly flat ground, the same sort of trips that my OD square gets 16+mpg.
I get the point you're making, but most likely OP is better off just sticking with his truck and paying for gas. Even with a cheap beater Corolla or Civic, you still have to pay for the car up front, pay to register it, and pay insurance. Even with double the gas mileage, unless he gets rid of the square (which doesn't seem likely) it will take YEARS to pay for itself, as would the gears (at least you don't have to insure those lol.
You could look into getting a little S10 or Toyota Pickup or something, but even those IME are sub 20mpg vehicles, and then you have even less power and tow capacity than the 305...
In this situation, there may be no magical answer to save money. Living in AK isn't cheap or easy from what I hear. Hell, I dream of living there but I know it wouldn't be easy