Pic is a little dark so I can't tell which color he is but he looks very pretty and healthy ! Scout is C. Collaris, probably eastern collared. So you could look for a cute female, try to get captive bred, some are in kingsnake classifieds. Just pick a pretty color that would look nice with Scout. Alot of females are a bit duller than the males, but not always, theres alot of real cute girls out there. Try and get one close to his age if you know it. Or atleast the same size range, ya dont want a girl alot smaller, he could harm her. Thats about it, same size or close, healthy looking, and Captive bred if at all possible.
Good Luck ! Let us know if you get one.
Eve