If you're not dead set on a plastic box, try repurposing a metal box. I took this 11-1/2" x 7-3/4" x 1-7/8" cash box and cut back the main till to hold my 1/2" deeps and built a little 2-compartment tray for the ratchet and for misc sockets, extension, and swivel. I drilled out the lock cuz it didn't come with a key and I don't need to lock it anyhow, then I took an old key and ground it down and epoxied it in place. A little magnet holds it closed. Nice and sturdy, but 11 lbs loaded so I'll really have to think through the handle I want to put on it.
It's for my road set of tools. I was considering an ammo box, etc until I came across this perfectly sized box.