Military surplus pure wool socks. Got mine from son in law who was active AF and wool made him break out in a rash. I got all his winter supply for years. Some are over 12 years old and still holding up well. I have seen some in surplus store over the years, but don't remember what $$ they were selling for. Just gotta remember to wash gently and drip dry.
There are only 2 kinds of waders, the ones that leak and the ones that are going to leak.
Even if wet, wool takes care of you.
If it gets real cold, near zero, some toe warmers add some comfort.