I guess the easiest to grab on the trail (during resupply) would be mountain house and backpackers pantry. They are stocked in every Wal-Mart in America. I am a fan of the Chili and the chicken with rice however I have not bought one in a good long time. They are bulky, flavor becomes bland by the end of the meal and at a price point of $6-9 they are not economical for me. I have gotten use to the Idahoen mashed potatoes(many flavors and variety of sizes). I pair this with a couple Tuna Selection Pouches(Many flavors and variety of sizes). Add in some packets of condiments to the food bag and you have yourself a pivot table of countless combinations.
Refer to Gambit's How To On Idahoan's for a neat way to use the tator bag as a bowl.
Idahoen's: $1.00
Tuna Selection: $1.29 (2 packs sometimes)
3 gram sachet of Tobasco: $0.28
A pack of Sausage and Cheese $1.50 (extra - not required)
So I got dinner at $5.36 for deluxe dinner and $2.57 for standard.