I doubt you will find a 2-channel "audio only" DVD-A and SACD player in the near future. The push for this type of "universal player" seems to be one that will play ALL discs, including DVD-A, DVD-V, CD, SACD, etc (maybe mp3, VCD, HDCD, etc). So you will most likey have no choice to buy a DVD-A player, that ALSO playes DVD-V.
Although, a 2channel-only DVD-A/SACD player without video or DVD-V would have its merits in the hi-end crowd. Maybe Accuphase will make one?
As a final note, some players with have some sort of "video-defeat" mode, to take the extra circuits out of the signal path for audio-only playback. Maybe you'll have to settle on that?