Just speaking up in agreement with Villagenut, it is a US Army Model-1851 swordbelt plate, issued from 1851 until replaced by the Model-1874. You found the version made for officers, which has in integrally-cast wreath around the eagle. Yours could have been lost in that cottonfield during the civil war, or during the postwar Occupation by yankee troops during the "Reconstruction" era.
You asked "Can this be professionally bent back into shape? If so who does this?" The only person I know who has enough professional knowledge and experience to tell you whether or not your badly folded solid-cast brass beltplate can be straightened (and properly do the work if it can) is Roland Frodeigh, who posts as RoFro at mytreasurespot.com. Tell him Pete George sent you.