Is it possible that using Fighter Factory to export an existing KOF2001 Original Zero sprite images is a do-able way? You can give credit to the maker.
OR here: http://biggysprites.smackjeeves.com/comics/768594/king-of-fighters-2001-original-zero/
*** not a complete sprite sheet though
[EDIT]: oh almost forgot Kong's big sprite-rip archive: http://www.mediafire.com/?84orz89rc78zg#w2yebmk0wor8s
I once used Kong's Breakers Revenge and Rabbit sprite sets to mugenize the bosses of the two (2) said
fighting games, thanks go to Kong!