The MV tile and character graphics are built around a 48 x 48 pixel square. And when you say Sprite, do you mean a character sheet, a character face, side view battlers, or some other thing? What, exactly, do you mean by 16 bit? I ask because people use '16 bit' to refer to at least three different things - none of which are the same thing - and expect everyone else to know what they mean.