Tried cheap bamboo pillowcases from Amazon
Well, it seemed worth trying, so I bought a pair of inexpensive ones. Washed one at 60°C in my Little Giant, and dried at "not-sure", because my recent model Whirlpool dryer doesn't have Low-Medium-High markings, rather a range of choices for each load type. I don't think it runs very hot. The pillowcase I washed shrank a little bit, but still fits over a hefty Casper pillow. Haven't slept on it yet.