I can recommend the NRS boundry water sock for wet wading. This is a knee high neoprene sock made for canoeing and kayaking with portages. It is fully seam sealed has a cuff seal at the top that actually keeps most of the water out. They come right up to the pit of my knee, the tallest sock i have found. I wear mine over some light poloypro sock liners for comfort.

They also make a vesion with a sole...