Dirk,
Sorry for the delay (life, etc.). Off-hand:
The RealiTone Ladies library I mentioned contains a operatic voice.
Completely forgot to mention;the East-West stuff (I have neither the Operatic Voices or Voices Of Soul libraries, so I can't comment):
Vocals - Soundsonline
It does regulary 50% sales but not necessaritl all titles.
Here's a Soundiron title for Kontakt Player. It integrates four, individually-available, non-Player libraries for solo soprano, alto, tenor and bass. Generally the same features as the individual libraries but, because it integrates all four, has a mixer tab/page:
Voices Of Rapture - operatic SATB solo vocalists for Kontakt Player – Soundiron
This one has a variety of phrases and features, so check it out: Soundiron stuff does go on sale from time to time.
Here's a Zero-G title that might address the opera issue for you. The format is simple Kontakt patches/instruments, so any adjustment have to be done with Kontakt's backend (spanner/monkey-wrench) but the samples are Acidized WAV files, so that opens up the possibility of further using Kontakt to create pitched versions of any sample. That does require a lot of auditioning each patch/key/sample:
Classical Vocal - Operatic Vocal Phrases
Here's two others I should have also mentioed previously for possible use with background vocals. It has a minimal GUI (mostly efx and filter) so the delimitations that I mentioned for the Zero-G library above also apply:
Vocal Forge
Vocal Foundry
I don't have personal experience with these, so you'll have to check them out:
https://www.kontakthub.com/label/Bela-D-Media/
Something different but possibly similar enough to your liking:
https://www.kontakthub.com/product/ERA-II-Vocal-Codex/
There are a number of short, sequenced video demos on the webpage. The Eduardo Tarilonte libraries don't go on sale very often. They run in the free Engine2 for Best Service.
Paj
8^)