Checking back in to say I got a pair of slippers!
I ended up getting these Tibetan Long Slipper Socks -
https://www.tibetansocks.com/product...-tibetan-socks
They are super warm and cozy - keeping both my feet and ankles super warm. The interior of the wool sock has a soft cotton liner sewn in all the way to the top, and a felt pad stitched to the bottom. I like that this is a company trying to helping impoverished women in Nepal, who make these by hand.