I got about 5 aluminum bottles w/ carbiner clips on them at the Disney Store for $5 each. Toy Story, Jack Skellington, Muppets, Minnie, and a Mickey. They work great for everyday and are super light when empty.
Disney The Lion King: The Broadway Musical Aluminum Water Bottle | Disney Store
They were on sale when we bought them, but normal price is about $10, but they’d be super cute, and easier to figure out who owns which one. Target has some, but they are about the same price for a solid colored one.