Help with protein and food allergies

I'm looking for good ideas for sports tournament snacks. Over the course of a day at a sports tournament, I'm on the field after breakfast all the way till dinner (usually no real lunch) and am looking for some food (protein) suggestions for snacking to keep me nourished during the day while playing sports. My main issue is that I'm allergic to legumes--peanuts included--and tree nuts. I also can't eat most protein powders (protein bars and shakes make me throw up). I've mostly kept to beef jerky and salted sunflower seeds, but meat is super hard to digest so I would imagine it's not the best snack. Grains are great, but I can't cook them on the field and don't have a kitchen when I'm away at a tournament so I can't really cook them before either. I've tried sunflower seed butter, but that reminded me too much of the taste of legumes, which is weird because I can eat sunflower seeds.

Any suggestions for things I could buy would be greatly appreciated!!