The term "survival kit" may also refer to the larger, portable survival kits prepared by survivalists, called "bug-out bags" (BOBs), "Personal Emergency Relocation Kits" (PERKs) or "get out of Dodge" (GOOD) kits, which are packed into backpacks, or even duffel bags. These kits are designed specifically to be more easily carried by the individual in case alternate forms of transportation are unavailable or impossible to use.
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!