>>1616727For reference, I'm thinking of a bivy like this:
https://mountainlaureldesigns.com/product/mld-bug-bivy/The shelter halves I'm looking at are Austrian surplus. Footprint looks to be larger on the shelter halves, but the bivy will probably sag a bit because the footprint is longer than the staked portion of the shelter half in a pup tent configuration, although I could also tie it off to a tree instead of staking the opening.