These are waterproof and have a great warranty (large lock & lock boxes). Not sure what size your looking for but they are durable. I've never seen this large of size before, but I've used the smaller variety for various purposes and like them.

http://www.amazon.com/Lock-38-cup-Rectan...0429&sr=8-6


Maybe even better yet and larger, (clear 5 gallon bucket)

http://www.amazon.com/5-Gallon-Clear-Pla...0783&sr=8-1

with gamma seal lids

http://www.usplastic.com/catalog/product.asp?catalog%5Fname=usplastic&category%5Fname=24&product%5Fid=20669

-Silent