Not entirely solo cello, but may well suit what you're looking for:
Music for a Glass Bead Game, Nathaniel Rosen, cellist, and Arturo Delmoni, violinist, (John Marks Records) (link)
Reverie: Cello Music for Quiet Times, Nathaniel Rosen, cellist, with guest (John Marks Records) (link)
Rosen Plays Brahms, Nathaniel Rosen, cellist, with Doris Stevenson, piano (John Marks Records) (link)
Orientale, short works for cello, Nathaniel Rosen, cellist, with Doris Stevenson, piano, (North Star Records) (link)
.
Music for a Glass Bead Game, Nathaniel Rosen, cellist, and Arturo Delmoni, violinist, (John Marks Records) (link)
Reverie: Cello Music for Quiet Times, Nathaniel Rosen, cellist, with guest (John Marks Records) (link)
Rosen Plays Brahms, Nathaniel Rosen, cellist, with Doris Stevenson, piano (John Marks Records) (link)
Orientale, short works for cello, Nathaniel Rosen, cellist, with Doris Stevenson, piano, (North Star Records) (link)
.