When I started working on the ships I bought a cheap Mickey one from the store on board for about $20. I got it so it didn't matter if it got ruined at castaway.
3 years later, way too many days at castaway, as well as being covered in sand, water, sea water, ketchup (don't ask), flubber, 'volcano eruption' juice, and other things that comes with working with kids, I still wear it every day and it still works...