Forgive me if I’m mistaken, but I believe the only OT music in the films that hasn’t been released at this point is a short TESB insert and two diegetic cues from ROTJ.
Yup.
And the few missing bits from Jedi (which I’d love to have) no longer exist.
In the fan-made isolated scores these bits are choppy edits from the actual film track. I’ve long planned to make better versions of these, but I haven’t gotten around to it.