I'm looking for a lid/brain from a climbing backpack to make a floating lid for one I already own. Maybe you've removed a pack's lid to go ultralight, or you have a pack full of holes but the lid is still good? 

Ideally it would be a reasonable size for a 30L pack, and have only one attachment point in the front, like this: 

Doesn't have to be a floating lid already but it would be rad if it were: