I went to REI this afternoon to buy sandals, and I found a pair that suits me. They're Tevas, and if I'm satisfied after wearing them a few times, I'm going to order another pair in a different color (these are basic black).
I tried on several other shoes, which ranged from not quite right to just weird (a pair of Birkenstocks that had their arch supports in a really weird place relative to my feet).
Having found a pair that I thought fit, I walked down and then up a flight of stairs, as a test, and they were fine. I try not to climb a lot of stairs, but some are unavoidable, and it seemed like a useful test.
I'd been a little worried that there wouldn't be anything left in my size, since we're well into the time of year when a lot of people are wearing sandals, but REI clearly thinks it's still sandal season, along with hiking and running shoe season.