Actually Jason's comment above appears to still be relevant. Although it appears as OOP here at FSM's website, SAE has Black Sunday listed as currently being available. The CD's status at SAE is more likely to be correct. There are 102 fewer of the 250 'impossible dream' compilations put together by FSM.
John Williams closed out a very busy 1976 with his compositions for the score to the thriller Black Sunday, which would get a delayed release until spring 1977. Host Jeff Commings is joined by Siddique Hussain, who counts the score as one of his favorites from the Maestro in the time between Jaws and Star Wars. He cites some thematic material and musical styles used in the score that will make stronger appearances in future films, including Star Wars. Since the film did not fare well at the box office, and critics were divided on the movie, Williams’ score got lost in the mix of his two other 1977 compositions. Thanks to a CD released by Film Score Monthly—and this podcast episode—you can enjoy the finer points of this score!