With a fridge, freezer & non perishables we can last for 6 weeks between re-supplying. The hardest is fuit & veg, & if unable to top up along the way we find a mix of frozen veg, (corn & green beans & spinach are better on space than a lot of the other veg/stirfry packs etc). Frozen veg is not as good as fresh (except for corn) but is good enough to keep you going when the fresh stuff runs out along with canned fruit & veg. When heading out from home some dried pasta sauce etc (in the dehydrator at home) help. & make a meal with pasta & whatever you have thrown in easy to make. Let me know if you are interested in how to 'powder' the dried sauce. There's a trick which makes it easier & more effective. We keep the powder in the freezer. Do the same with homus because it works very well, reconstitutes so you would never know it had been dried. (We buy the kilo buckets of Yummis Hommus - it's good) from the supermarket Of the canned veg I reckon mushrooms are about the best. A good supply of powdered potato (Deb), rice, pasta & flour.
Another bread alternative which is good & can be made in a frypan is a mix of flour & Yoghurt. (Let me know if you want the recipe). Easy & quick. We carry one of those Easiyo insulated Yoghurt makers & the powdered yoghurt (greek style) - make a kilo at a time just by boiling the billy. The insulated container is a little bulky, but we find it worth it for the extra variety we can have in our diet (especially as I'm gluten free).
Wrap fresh veg in foil - keeps longer & better in the fridge.
If you can manage the space it's good to cook larger quantities of the fresh veg which doesn't last as long, & put the extra into the freezer for later - so carry a supply of freezer bags - or even a few of those disposable containers. They are lightweight & easier to faff around with than bags.
Our freezer isn't huge, 35 litres, (& fridge is 60litres). When getting meat cryovaced, ask for it in meal size portions & packed as flat as possible. It helps & is surprising how much can be fitted in. We have a vaccuum sealer thingo at home, but have found that meat cryovaced on the commercial machines by butchers to be better. We generally pay $50c or $1 extra for each cryovaced bag. Adds up in cost, but it is cheaper than buying meat from tiny community stores a long way from anywhere. You'll probably get a bit of fresh fruit & veg at Kunuwarritji (Well 33), but the cost will be high. Don't plan to buy other stuff there - it will be 3 times the prices you are used to.
Consider supermarket frozen fish too. Eg. Flathead fillets. If you can get a kilo pack with each fillet in it's own cryovaced pack (have only found these a couple of times) it makes it easier to find space as individual fillets from the kilo bag's contents can be squeezed into 'spare spaces'.
When driving or camped in the sun we run the freezer at minus 14, & put it onto minus 10 overnight. Have had no food wastage doing this.
Tinned fish (tuna etc) is good. Wraps keep better than bread.
MrsTea often makes savoury rice balls after we've had a rice meal where she has cooked extra rice. Rice + egg, cheese & Jalapeno chilli (I think) when we have the camp oven out. They can be eaten cold & are good for a couple of days in the fridge, so are a reasonable lunch option. ......... as are cold sausages.
We avoid meat with bones for cryovacing - can pierce the plastic. Sausages are best pre-frozen before cryovacing if you don't want the contents squeezed out of the skins.
Just my jumble of thoughts - hope something in there helps.