a few that i've wanted to use for this purpose. i work on them, off and on:
Hot Tuna: Embryonic Journey, Good Shepherd, Water Song Dead: Sage and Spirit
it occurs to me that probably nobody knows this last one. you can hear it at:
oh yeah. another good one would be Tull's arrangement of "Bouree".
-- Optimism and pessimism don't exist for me. I'm a blues man. I am a prisoner of hope. I'm going to die full of hope. - Cornel West