At Kelso Depot, I'm happy to learn that they do sell AA batteries, and I chat with Preseve staff
After discussing a few options with helpful Preserve staff, I decide to ride to Kelso Dunes and camp there tonight so I can hike the dunes tomorrow.
I've never gotten around to hiking up Kelso Dunes though I've passed them on previous trips out here. This trip is my chance to finally do it.
Before leaving, I buy several packages of AA batteries to power my camera and my tent's flashlight lantern a couple of days (they both use a lot of batteries).