A retail price is still not available, but the release date is set for "August 2013".
Here is the track-listing:
Disc 1: The R&B and Country Sessions - The Outtakes: 17 tracks.
Disc 2: Part 1 - The Pop Sessions - The Outtakes: 10 tracks.
Disc 2: Part 2 - The July 1973 Masters: four single sides and six album tracks.
Disc 3: The December 1973 Masters: seven single sides and 11 album tracks.
ELVIS AT STAX: DELUXE EDITION by Elvis Presley
(RCA/Legacy 88883 72418 2)
source: ElvisDaybyDay Blog and Elvis Matters