If it is white plastic and less than 10 years old I would assume it is a food safe 2, 4, 5 number, whichever are the food safe ones, don't remember the numbers. Even without knowing the numbers, I would go for it.
I use currently an 18-gallon clear tote from Target, was on Clearance for $6.00 each, got 3 of them, and use others for some mixing and what not.
If you are unsure run and grab a clear tote with a good plastics number.
For the cooler, just make sure there is no water storage occurring on any portion that is metal, no metal ring at the bottom drain no metal around lip at top, just nowhere. Any metal or any suspect metal, spend the $10 on a tote.
Good luck.