When I first started out I used elf brushes. I have a really nice set of sigma brushes but I actually tend to gravitate more towards my elf brushes when using shiro products because they pick up the pigments better in my opinion. And they're SUPER cheap. I also recommend you get some sort of pill case or little jars to put your sample bags into because it becomes a pain in the butt getting the shadows from the baggy and it gets VERY messy after about the third application. this is similar to what I use. It works extremely well!
Each day (with two compartments per day) on this pops out, so you could just take 1 or 2 with you.
This could also be an option - you can have 1, 2, or 3 sections.
I also have one that I can't find the link for that might be overkill. It's similar to the second one above in size and shape (maybe a bit larger), but opens in half with separately sealed sections on each half. One was divided, the other wasn't - I used to store q tips in the undivided side. I'm sure someone still makes them. If that sounds like something you might want, I can try to find something similar.
Edit: like this but one side was all one section.
Not sure if the way it closes is secure or not, unless you put a band around it