You know, Ted, looking at Yogi Bhajan's Kundalini Sikh's bio and timeline, I believe Mike Heron wrote it first !! Well.

Here's a link to the song:

https://youtu.be/jmeGpov2P5k?feature=shared to Long Time Sun begins at 10:20 -- What do you think? This is a 1968 album, so probably written in 1967.