I've never been to Alaska, but I would assume you could possibly expect snow/ice no matter what time of year you go...especially as far North as he is going. I used to backpack in the snow, and I can tell you that you MUST have a 4 season tent, as opposed to a 3 season, if you remotely expect wintery type weather, or extreme winds/rain. With that in mind, I would look at REI for a 4 season, two man, backpacking type tent. And I would expect to pay more than $250 for a quality tent made to withstand that kind of weather. In that world, you really do get what you pay for...better poles, better stitching on all the seams, sealed seams, generally a vestibule (sp?) area under the rain fly to keep wet boots or other things you don't want in the tent with you. It also doubles as a cooking area if it's bad weather outside. With a couple of practice runs setting the tent up at home, it is really easy to set up today's dome style tents. It also pays to get a heavy duty piece of poly, cut the size of the tent's bottom, to use as a ground cloth under the tent to keep abrasion down to a minimum, and also to keep the bottom of the tent floor clean. REI probably has ground cloths for any given style/shape of tent already cut to fit.
Regarding sleeping bags: Prime Goose Down is still the best insulator for the weight that there is...no man made product comes close. It also packs down to a smaller size in the stuff sack...BUT, you MUST keep it dry at all times, otherwise it is useless. If I were headed up there, I'd look for a mummy style bag rated to at least 15 degrees F...that will weigh about 2.5 to 3 lbs, and be half the size packed than a similarly rated bag with man made insulation, and about 2/3 the weight. Again, expect to pay around $250 for a good Goose Down bag.
All I'm sayin' is that you generally get what you pay for with this type of stuff, and if he's going to be "out in the wilds", even if it is just off the road, it's not worth being miserable or putting your life in danger to save a few bucks. Been there, done that... He is about to embark on the adventure of a lifetime...I envy him and hope that he gets lots of pictures to share.