NOW IN HD AKA Cult of the damned Plot: The homely daughter of a rich, vain woman gets mixed up with a kinky, menacing pop singer and his weird friends.
You can stream Angel, Angel, Down We Go (1969) 1080p BD RIP (1969) free and legally on OldReel, via the Internet Archive.
Yes — it is in the public domain and can be watched and shared freely.