How are you cooking? If you need boil and rehydrate then you will either have to pay more or spend a time making it up yourself. If you are cooking over a fire and cooking time is not an issue then you can take rice and beans, both of which can be bought cheaply in bulk. I'd also watch for farmers markets and roadside stands as you travel to suplement your food with fresh fruits and vegetables.
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If I wouldn't eat it at home, why would I want to eat it on the trail?