Not sure if this is what you're after or not but Anja Lechner ( of the Rosamunde Quartet) has put out 2 albums with Vassilis Tsabropoulos ( piano) of music that certainly fits the genre you're after."Chants,Hymns and Dances" ( ECM New Series 1888) and "Melos" ( ECM 2048)RA both hauntingly evocative , beautiful albums based on the music of both Tsabropoulos and Gurdjieff.Tsbropoulos is a Greek , classically trained pianist who now inhabits the jazz world comfortably ( in a similar vein to Ketil Bjornstad).Lechner's style is classical in structure but she adapts to the slighly different fare with aplomb. So not solo cello music but with a stong cello component. You mention David darling - I assume you've checked out "Epigraphs", his duet with Bjornstad.
Cheers
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