Hi harpgirl,It looks like Pentangle did 'When I Was in My Prime' on their CD "Collection" and on their CD "Pentangle". Nina Simone also recorded this song on two of her releases (Gold Collection and Tomato Collection - both 2 CD sets).
(Incidentally, I have a real hard time imagining how anyone might "look cute" singing about their enjoyment of going out with one or more of their friends with the express purpose of sexually assaulting a woman en masse against her will. Or maybe the song you refered to has a different meaning of the term "gang bang"?)
Rose