This won't be any help to your specific request, but at least opera related.
I don't listen to full opera performances, but do own nearly every
Maria Callas vocal collection on the market. I am under her bewitching spell and love her tempestuous firey nature, her deep heart felt passion is present in every note she sings.
Unfortunately there exists almost no video footage of Callas many prime 1950's La Scala performances. There is a famous later performance filmed by Franco Zeffirelli documenting 1962,1964 performances at Covent Garden:
This film showcases Callas remarkable acting/dramatic skills but by this time her voice was noticeably in decline and personal tragedies had broken her spirit and left her a shadow of her former self. Fortunately we have many very good mono and stereo audio recordings by EMI which preserve many great performances during Callas prime years.
Ovation Channel sometimes shows the documentary
Maria Callas: Life and Art which traces her entire career mostly through interviews and still photos of prime years, and at the end of her career shows parts of the Zeffirelli filmed Covent Garden performances. Much of the commentary provided by her friend Franco Zeffirelli, biographer, and fellow artists she worked with. There are a couple similar documentaries out that cover mostly the same ground.
A collection of opera scences staged for B/W TV in Paris 1958 exists called "La Callas... Toujours" which would showcase Callas in close to prime vocal form. Have not seen this but it is supposedly the best available video document of Callas near the top of her game vocally.
For audio collection if you want to start out get used "La Divina" set at Amazon, 4CD set, 3 vocal 1 interview. Also each of three audio La Divina CDs available individually to start with small purchase. Contains both mono and stereo performances, but good mono is not bad for solo vocal pieces and you will hardly notice it.
Sorry for the diversion but must take every opportunity to promote this great artist.