Cotton is bad to stretch with sweat and end up causing blisters and other unfortunate results. Actually acryllic is the best for wicking and foot care--at least that's what they used to preach in Runner's World magazine.

I found 2 pair of khaki hose in a very light weight wool that were sold as uniform socks from Bermuda . . . or somewhere like that. Seems like I got them on ebay, but I've see them around before and since; just can't remember where right now. (I'm old, the meds are kicking in, I've slept and eaten since then, etc.)

Try "knee socks" or some such for seaching.