Dunno if this will be any help but, for what it is worth , When I was in New York some years ago I went to "Sam Goody's" to browse through records and tapes. I found a selection of Old Radio Shows on Cassette. I bought several, featuring Burl Ives, Pete Seeger, Woody Guthrie, Cisco Huston and "Lefty Lou"   from old Missou. (who she ??) among others. There seemed to be a very varied stock but, does Sam Goody still trade I wonder??