There is your solution, do like what Wade did.
You can find used drums at the car wash or truck wash places or even on craigslist.
Install a bulkhead fitting at the bottom and a hudson valve in the top so it does not overflow (if your machine will pull from a tank).
Just make sure if you go this route, secure that drum or tank securely so it does not flop around when driving.
Post some pics of the rig so we can help you with some more ideas.
OR
You could get more hose for the bypass loop, maybe like 10' long and that would give you a couple minutes of bypass time, check with Russ to be sure but I think you would have a couple minutes before you need to pull a trigger or turn off the machine so you don't cook the pump seals.