Very nice bird, congrats!!!
When I was going to grad school in Mississippi, I was a member of a hunting lease about 10 miles east of Starkville, MS. On this property, you would occasionally see birds having similar coloring to yours. I was told by one of the elder members of the club that a storm had ripped the roof off a turkey farm releasing several white birds, which ultimately bred with the native, wild population. Some of the birds had even more white than yours, and I once saw a hen during the deer season that was a cold gray all over, very cool looking birds for sure.
I never got a chance to kill one, but was close one morning on two strutters that were hened up about 100 yards from the property boundary. That's the closest I ever came to taking such a fantastic trophy, much like yours.
Congrats again on a very cool bird!!!!