Trying to think outside the mainstream for psychedelic, not necessarily the 'most' but less obvoious : Holts's Neptune The Mysic, Saint Saen's Danse Macabre, Stravinsky's Firebird Suite, anything by Ravi Shankar or late Coltrane or Alice C /Pharoah Sanders. I'm trying to approach this from the point of view of psychedelic meaning altered state of consciousness without necessarily a direct LSD reference.
I'll give it more thought.