The T.S. Eliot play Murder in the Cathedral is quite an impressive work. It treats the last days of St. Thomas Becket in a symbolic and thought-provoking manner. I think it would be wonderful to see if performed live someday. Still, it is possible to listen to an audio adaptation here and now, (if you can find one, that is).
I know of three. One was done in the 1950s, one in the 1960s, and one in the 1970s. All were released on vinyl. One was re-released on cassette and now on CD (in the UK) and MP3.
The first is performed by Robert Donat and the Old Vic Company. This was released in the 1950s, and one can find an occasional set on Gemm, Musicstack, or Ebay. However, it was re-released on cassette, and used copies are available through Amazon. Now, it has been released on CD and MP3 files. Amazon (UK) has the downloadable MP3 version.
The second is from Caedmon Records. It features Paul Scofield and the Theatre Recording Society. Vinyl copies can be found in the usual places, but often they are $20 or more. It has not been re-released. Someone put this version out on Youtube as a series of files.
The third edition is from Argo Records. The play is performed by the Royal Shakespeare Company and features Richard Pasco as Thomas Becket. (I have this edition.) Some parts that are soft and “in the distance” are a bit difficult to hear. It requires some volume adjustment to enjoy, but is quite well performed. Copies are found in the usual places.