To me, this is the Holy Grail of Masterpiece Theatre presentations. I'd trade all of the ones in existence for this one - why Thames won't (or can't) make it commercially available, I don't understand. I'm sure somebody somewhere has a bootleg copy (this being shown first time 'round - and to my knowledge, only time around) in the fall of 1981. This was broadcast in the days when VCR's were available (at great cost, but available nonetheless). Wish I were friends with Dame Dench - both she and her late husband had featured roles. Somehow I'd bet she has some footage (or could get her hands on some).
In my recollection, this production was pitch perfect. True to the books (unlike the recent Moggach adaptation - true to the concept, but these were works to savor, not condense, and that's what Moggach did, just like in the new "Pride and Prejudice") and perfectly cast. Sheila Gish was a good Lady Montdore, but Vivian Pickles was even better - no introspection whatsoever. Boy (in the original) was somehow a little more "lapdog" than Jeremy Irons (who nonetheless steals a number of scenes)and John Hurt was the definitive Cedric. The narrator in the original was perfect (unlike in the recent remake, where Rosalind Pike's beauty eclipses both Polly and Linda, which skews the story somewhat). There was balance in the original between the older characters and the younger characters; in the newer version, I thought the elders stole all the scenes, which is problematic. The original version is definitive, superlative - but unavailable. A sad state of affairs.
If anyone ever gets their hands on it, please let me know!