Most of these documents have been confirmed as referring to the Kelsey Museum of Archaeology in Ann Arbour. Follow link on the right to Ann Arbor, MI, Kelsey Museum of Archaeology, University of Michigan for further information.
Relevant publications:
Hyatt, Adam P. 2014. The Michigan Papyrology Collection and Karanis. In Wilfong, T. G. (ed.), Karanis revealed: discovering the past and present of a Michigan excavation in Egypt, 35-38. Ann Arbor, MI: Kelsey Museum of Archaeology.