The interweb comes through again!
So, in browsing iTunes and Amazon, I found the 1996 (as I recall) Das Buch mit sieben Siegeln, with Horst Stein leading the Wiener Symphoniker. Score!
Now, I would like to point out, once again, that Dimitri Mitropoulos' legendary 1959 Salzburger Festspiele recording is still unavailable -- either in electronic form or on a CD (which is, I know, as electronic as a MP3) -- but I won't harp on unpleasant matters. In fact, if ArkivMusic really wanted to make this blogger happier than he already is with them generally, it would most certainly put out the Mitropoulos Das Buch with full documentation on their ArkivCD series. I digress.
It is unfortunate that there isn't an unreservedly great Das Buch mit sieben Siegeln out there, as it really is one of the neglected triumphs of the 20th century. Horst Stein leads an interesting account, but, like Järvi, I don't feel like the climaxes were played to their fullest. The Wiener Symphoniker does a good job, as do the singers, but one gets the sense that the relative obscurity of this work creates a certain uncertainty. There are a lot of big moments in this piece, too, and to let one of them go by without really hitting it hard (as I get the sense Stein does in a couple of places) seems like a waste. In other words, there isn't an unreservedly great Das Buch mit sieben Siegeln out there. I don't regret the purchase, since I am happy to get any recording of this work, but it drives home the fact that there is a wide opening available for a conductor who understands Schmidt's idiom and has a great cast and band. If DG would give Fabio Luisi the WP, René Pape, Ben Heppner, and a great quartet, then I am sure that there would be a good record in the final balance.
That having been said, I am sure that there are at least two sets (Nikolaus Harnoncourt's set, which went straight to Berkshire, I'm told, and Mitropoulos') that major labels have. Direct-to-digital releases aren't a bad idea, as Profil has shown us with the Stein set. Let the hard-core Das Buch nuts have their records without going to the cost of printing and marketing sets of an obscure 1937 oratorio.
Now that I've wandered around a while, let me say that -- for the money -- Stein's set is a solid download. Burn it to a CD, put it on your iPod, and listen to it for a while. There is a lot of great music to be found in Schmidt's magnum opus.