You might want to take a look here:
http://en.wikipedia.org/wiki/One_Tin_SoldierLooks like you are looking for the original version by Coven.
From Wikipedia;
"Jinx Dawson of the band Coven sang the song at a 1971 session with the film's orchestra as part of the soundtrack for the Warner Brothers movie Billy Jack. Jinx asked that her band, Coven, be listed on the recording and film, not her name as a solo artist. This Warner release, titled as "One Tin Soldier: The Legend of Billy Jack," reached #26 on Billboard's Hot 100 in fall 1971, only to be pulled from the charts by the Billy Jack film producers as it was moving up due to legal squabbles over the rights to the recording.
The full Coven band then reluctantly re-recorded the song for their MGM album. Thus the MGM album containing a second version of this song displayed their whited-out faces on the cover, contrived again by the film's producer Tom Laughlin. The recording then hit the charts again in both 1973 and 1974 after the end of the Vietnam War but before the release of the film The Trial of Billy Jack. The Coven recording was named Number One All Time Requested Song in 1971 and 1973 by the American Radio Broadcasters Association. A slightly different version recorded by Guy Chandler (titled "One Tin Soldier (The Legend of Billy Jack)") charted in summer 1973."