My daily snacks usually include the following.
Stick of cheese
Serving of almonds
Serving of dry roasted edamame
Two cups of Chobani yogurt
I don't know what you can take with you that won't perish without a way of keeping it cool.
I'd like to take Muscle Milk but that looks like the fastest way to end up with a cracked skull in this land of security theatre and pseudo-police brutality. Might just have to get some extra packs of beef jerky.