AR15, first choice, best choice.
Not to mention caliber change inserts, and possibility of using flares.12 gauge pump shotgun. You can take big and small game, it will stop any person that gets close, (I wouldn't plan on getting into a long term fire fight or sniping since being gray and not seen would be the safest tactic), ammo is available at damn near every house in the country, very few parts to break, it's rugged and reliable. JMHO.