Hacksaw,

Here are a few ideas for sustainability in your BoB.

For a stove, consider the Bushbuddy. It's a wood gasification stove (no fan or batteries needed) that is pretty efficient. A bit pricy IMO but possibly worth the money ($95Cad to $105.45Cad, depending on where you live.) when it comes to durability and fuel sustainability. If you understand the principles involved and you are a bit "crafty", you can make your own out of a couple cans, a couple pieces of hardware cloth and some JB Weld.

Bushbuddy compact wood burning stove.

YouTube Video of the Bushbuddy

For water purification consider a Millbank type filter bag. Combined with boiling, chemical purifiers or a jury rigged solar shower and activated charcoal filter (Water from the Millbank drips into the solar shower and through a charcoal filter cartridge for a refrigerator’s water dispenser/ice maker attached to the output hose for the shower, the purified water then drips into your pot, canteen or hydration pouch.) a Millbank would give you all the potable water you’ll need in above freezing temperatures or if used inside a heated shelter. Add an MSR Miox or a SteriPEN for final treatment (if you’re not boiling, treating with chemicals or shower/filter rig) or water sources free of chemical/heavy metal pollution and you’re good to go.

For a dietary fat source consider a bottle of extra virgin olive oil. It doesn't need refrigeration even after being opened as long as it's kept shaded and relatively cool (Think bottle cozy with evaporation cooling attached to the outside of your pack in warm weather.). A tablespoon, maybe as little as a teaspoon in your food every couple-three days should stave off "rabbit starvation" for quite awhile so a quart would last for at least a few months, more than long enough to find additional sources of dietary fat. Nuts are a good source of fats, if you have edible nuts in your area. Raccoon, skunk, woodchucks and other middle-sized critters get pretty fat in late fall but nothing beats beaver tails for a high fat tasty treat, unless you can trap or shoot a bear.