Appendix Out - Scottish folk psychedelic band.
The album The Rye Bears a Poison - likely reference to the ergot fungus that grows on rye from which lsd is synthesized

Maybe?



I dunno.

Or maybe?

?

Last one

Trees...yes. The recent Trees box has got it all. Skip a few meals and get it. So great

Indian Summer by Panama Limited (recorded by John Peel)
All On The First Day by Tony Caro and John

Fully agree with The Hangman's Beautiful Daughter by Incredible String band as an entry point. It was the first thing I was gonna mention. Not very dark, exactly, but the early Tyrannosaurus Rex stuff like Unicorn or Beard of Stars or "T. Rex" might be up your alley.

That Buffy Sainte-Marie album is fantastic. It was considered an utter failure upon release and was all but deleted from her discography. That leadoff track, God Is Alive, is a Leonard Cohen poem. The guy who produced that album also did some cool Richie Havens stuff. You should also probably give the album Richard P. Havens 1983 a try. Start with the song For Haven's Sake.

Not psychedelic, but everyone should check out Sibylle Baier if they haven't already.