314 No way. 312 you'd have to use 90.4 and I really think you'd be streaching it. Which one is it a Cabinet(see definitions) Cut out box (No), Meter Socket encloser (No).
So then a MCC must be a Cabinet .
Cabinet (an encloser that is designed for either surface mounting or flush mounting and is provided with a frame ,mat, or trim in which a swinging door or doors are or can be hung. Doesn;t sound like a MCC does it??