REI Anchorage closes at 8 pm on Saturdays, so that’s out.
Inga House is really convenient to lots of venues and restaurants downtown, but somewhat far from the malls (except the 5th Avenue Mall which is mostly clothing stores). Let me know how it is – those are crazy-low rates for Anchorage in the summer. Their weekly rates are less than most nightly rates!
The Walmart south of Benson, east of A street is kind of shabby and racist but midway between the airport and your lodging. Bear spray and butane fuel are normal stock items for them, not sure how they’re doing this year between everyone’s supply issues and travel to Alaska rebounding a lot.
The Walmart (open till 11 pm) south of Dimond Center, south of Dimond Blvd and west of Old Seward Highway, is a bit more suburban. Due east across Old Seward Highway is Sportman’s Warehouse (open till 9 pm on a Saturday) and, at least in Soldotna, does a better job of keeping all three sizes of butane in stock. You could start by Uber’ing there first for bear spray, butane and an AR-15 (or a real bear gun like a .338) and have Walmart across the road as a back-up. Sportman’s has a modest selection of FD food, but none of the $1 Pasta Sides, granola bars, and basic cheap groceries that Walmart does.
If a trip to Anchorage comes up for me in the next 8 days, I’ll let you know – I could leave bear spray and fuel at Inga House for you – I’ve done that before, but at this point, I don’t have anything planned.
There is a store in Denali NP near the campground at the park entrance. They’d probably have fuel and bear spray but you have no alternative once there, other than doing a deal with a departing tourist. Maybe give them a call and see if they’ve been keep fuel and spray in stock recently.

