This group stresses being able to stay alive for indefinite periods in life-threatening wilderness scenarios, including plane crashes, shipwrecks, and being lost in the woods. Concerns are: thirst, hunger, climate, terrain, health, stress, and fear. The rule of 3 is often emphasized as common practice for wilderness survival. The rule states that a human can survive: 3 minutes without air, 3 hours without shelter, 3 days without water, 3 weeks without food. 
Modern-day survivalists aren't generally regarded as the most sane people on the planet. A quick look at any one of the disturbingly common and frighteningly thorough shopping lists they post online drives home the fact that anyone who self-identifies as a "prepper" most likely went off the deep end a long time ago. Sure, it's fine to keep a few extra cans of food and cases of water around for an emergency, but if you start adding body armor and butt paste to your stash, you might want to tell George Miller that it's time to see other people.
Tenacious Tape is not the kind of survival gear you won’t use every time out but when that rogue branch falls on your camping tent and rips your fly you’ll be thanking your lucky stars you have it in your bag. It can prevent a difficult situation from turning into a life threatening one. Tenacious Tape is completely weatherproof and won’t ever wash out. It doesn’t leave any tacky residue and is also machine washable. It’s the kind of quiet innovation that elevates the outdoor experience for everyone without making a lot of noise and is essential survival gear for any outdoor aficionado. Available in 3” or 20” rolls and a variety of colors.
Astronauts are provided with survival kits due to the difficulty of predicting where a spacecraft will land on its return to earth, especially in the case of an equipment failure. In early US space flights, the kit was optimised for survival at sea; the one provided for John Glenn on the first American space flight in Friendship 7 contained "a life raft, pocket knife, signaling mirror, shark repellent, seawater desalting tablets, sunscreen, soap, first aid kit, and other items". A survival kit was provided for the Apollo program which was "...designed to provide a 48-hour postlanding (water or land) survival capability for three crewmen between 40 degrees North and South latitudes". It contained "a survival radio, a survival light assembly, desalter kits, a machete, sunglasses, water cans, sun lotion, a blanket, a pocket knife, netting and foam pads".
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!