I just bought a pair of rubber Wolverine hunting boots from sportsmansguide for $40. I have not tried them out walking around other than the yard but they are comfortable and 1000 gram of thinsulate so I know they'll be good for cold weather. I also have a pair of what you'd call boot blankets or insulators from Arctic Shield ($40). These will make the cold November hunting days in Minnesota where we could easily be in the teens much more bearable. When I get to stand or the blind,I slip the blankets over my boots. They are supposed to retain heat on their own but I always slip one heat pack into each over the toe of each boot and I can sit for 8 hours with my feet feeling nice and toasty before I add a new heat pack.

Socks are also key, as is a boot size one size too large for good air circulation. I wear a medium weight polypropelene sock under a much thicker and heavier wool sock and these will last me all day without changing.

Good luck.