One of the tricks I use to keep the feet warm is to use a plastic shopping bag as a first layer. Put sock layer over that. It keeps the perspiration from absorbing into the socks and boots. The feet will get kind of pruned up, and I've never tried it in consecutive days, but it works. I've read of folks hunting Canada using a plastic garbage bag as a first layer on their torso. Same concept.
Good luck ! Rusty
Rusty