For specifically Czech recordings of Janacek, you might check out what's
available on Supraphon. My Suk recordings on Supraphon all use Czech
orchestras, and my copy of the Glagolitic Mass, although conducted by
Charles Mackerras, is performed by the Czech Philharmonic Orchestra and
Prague Philharmonic Chorus. I'm pretty sure that Supraphon has released
Jenufa and The Makropulos Affair.
Patricia Price