Antique Victorian Fancy Illustrated Envelope PM Ann Arbor MI Birds Flowers For Sale

This is a sweet envelope,- nothing inside however. 5.25 x 2.75" in size. I am guessing from the 1860-70's. It has a double circle date stamp stamped Ann Arbor MICH with a date in the center, but I don't believe a year. No stamp. Must have fallen off. Still a lovely specimen of a day gone by. It would be fabulous to frame/put in an assemblage etc. which I might do if it does not sell.
Good condition. Discoloration due to age. Dings. Zoom into photo to see in detail and message me with questions.
Shipped inside of a heavy envelope as a first class letter, (no tracking/insurance) or with backing inside of a card as Ground Advantage with insurance and tracking.