Two short audio selections of C S Lewis speaking have recently been posted to YouTube. These must have been given when he was broadcasting the talks that became “Mere Christianity” during WW II. I have included them as a link under Show Notes and as a link below. Note that some of the material is different from what appears in the book’s text, which is probably due to Jack’s revising the material before publication.
If you are aware of how the tapes were located and produced, I would appreciate knowing about that.