If you like a bit of opera and have a Qobuz UK account, then it looks like there’s a bargain (probably a driving error ??) on Maria Callas / Completed Studio Recordings in Hi-Res audio.
Thats 1100 tracks for the sum of £7.34…….
Whilst it is obviously listed at that price in the enclosed link, I cannot guarantee that not will work – my Qobuz account is with the French site and so defaults to that, where the price is still 142 Euros.