Did you not buy this entire set then? http://oryxdesignlab.com/sprites/16-bit-fantasy-sprite-set
Because it does feature female versions of most creatures. Hell, Before I even saw this full sheet I drew up my own female keeper based on a blurry screenshot of the male one, trying to keep the style and colors the same as the rest of the Graphics. (I Think my female Keeper is better than the one in that sprite sheet to be honest.)
