This is a video of part of the 1980s production of Lillian Hellman's play
The Little Foxes starring Elizabeth Taylor (in a truly ghastly faux Southern accent). It was obviously shot by somebody with a camcorder in the audience. Humbert Allen Astredo appears, somewhere around the five minute mark I think. I haven't had the chance to do more than have a glance at it--he is debonair and flawless, as always.
https://www.youtube.com/watch?v=8_yi-Ga6Iy4&G.