Not sure how much gear you've got or what your budget is. Have you checked out rolling toolcarts or toolboxes? Found a couple on amazon for around $40-50, plastic with multiple compartments. They have a small handle and wheels like a smaller suitcase. Stalwart makes one that's a combination of a couple boxes with an overall size of around 17.5" x 10" x 24.5" tall. Another called a keter masterloader has multiple storage areas, also around $50. Husky makes a 25gal one that's got 8" wheels, it's 35" by 22" by 15" for around $60.
If it doesn't need to roll and you just need something temporary for cheaper, maybe check those plastic drawer bins at someplace like walmart, I think sterilite makes them. They have different sizes that stack, you could tape the drawers shut with packing or duct tape for the trip then repurpose once you get to where you're headed. Might have to pack things like mods wrapped in socks or old tshirts to pad them, put juice bottles in plastic ziplock bags in case they leak and use older clothing to fill in the gaps so they don't bounce around so much.
You could likely pad several mods, batteries (in plastic cases) and juice (in bags) in a smaller plastic toolbox, stanley's got some that are like $10 for a 16" smaller toolbox. They're pretty tough for a cheaper box, I've got a couple I used for screwdrivers, wrenches and things and used it to tote a few tools back and forth from work to home. The case is firm enough to set things on top of it without crushing it. I mean I wouldn't stand on it but it didn't fall apart around an auto shop.
