BBC - Transcription Service - Others discovery
BBC Transcription Services (before BBC Transcription Service (no "s"), later BBC Transcription and today BBC Radio International) discs were only made available to overseas radio stations for broadcast purposes and were not made available for sale to the general public. However, in the early 90s many international BBC libraries sold their stocks to the public. Limitation: "Typically BBC Transcription Services pressed 100 copies of each disc only with instructions to the overseas radio network to destroy the disc at the end of the licence period."
Note that the genre of shows available via this label is as wide as the main BBC labels available to view here.
Also, records have been issued home and abroad for many years (the oldest I have has a date of 1949 but they have been issued for much longer!) Unlike most catalogues of records, each side of the BBC Transcription disc has it's own catalogue number - side two normally is one number higher than side one!