What about materials off the Maple Leaf in the St. Johns River,
Jacksonville, Fla.  There should be reports on this excavation in
publication and it was filled with Union supplies and camp kits when it
sank.  Not exactly an ethnography of camp life, but it should provide
comparable data on material culture; also, preservation was good, so
items which might exist as only fragmentary or partial objects on a
terrestrial site would probably be represented in more complete form from
the ship.