I picked up some of the lyrics but google search isn't helping with:
"polished bright for love" or "we climbed to that place in the sky"
No soundtrack ever released and the video you posted doesn't do all the credits (or they didn't bother for music in 1969).
I did find out the film score was composed/conducted by Raymond Leppard https://en.wikipedia.org/wiki/Raymond_Leppard
but I can find no actual reference to the song itself or who performed or composed it - and whether it was ever released.