The vest itself is a combination of MOLLE equipment over a tactical vest. Some of the US RV'ers use those fly-fishing vests as an alternative too. Ultimately what I use may not fit anyone else, or they might have different priorities in what they want to carry, but the beauty of the MOLLE system is you can customise it to suit your own needs & wants.
An example is this bare vest is on Ebay for $40, and you can add whatever pouches you want and will fit in your cockpit. You'll notice I haven't focused too much on food, though there is a small snare in one of the pouches. You can go 3 weeks without tucker, and I hope I would be home by then! Survival to me, isn't about camping in luxury, it is about making sure you are still alive when the paramedics find you, so I have put more medical, first aid and location aids in there than rations. For remote areas, I would carry water in the back of the plane, but not on my person. You can still go 3 days without water and again, I hope AMSA would have at least found me by then, even if the ground party is still some days away.
To that end, I typically use OzRunways with tracking enabled, I have ADS-B in the RV, and for XC flights, I file a plan, rather than just a flight note or worse, nothing at all - even if ASA does get confused because not many RAAus aircraft request flight following...The recent Mooney prang inland from Coffs shows the benefit to ADS-B in the search effort, even if it wasn't a happy ending...