Madelyn Zoi cited Pringles cans as being one of the best things to pee in on those cold, cold camping nights. They’re laminated, large, wide-brimmed, and the top can be popped right back on. Plus, you’re also packing a snack. Remove/eat Pringles before “using.”
Any ol’ place that sells quality(?) snacking provisions. Let’s be real: check your own pantry first.