Regardless of whether everything is going swimmingly or you’re lost in a whiteout above tree line your boots are one of the most important pieces of survival gear you have. You need them to stand up to the elements and keep your feet dry and comfortable. Irish Setter Men’s Waterproof Hunting Boot is a fine example of the state of the bootmaker’s art.
To me, the best option is to store emergency food. How much? If you have none, store enough for a few days. If you have enough for a few days, get enough for a week. How much you store depends on what time frame you think you're at risk for having to be completely independent. The early settlers of the southwest liked to store enough food for a whole year and still do to this day!