Ok, the whole album have been released on iTunes too.
But it's separated in 4 differents albums (one for each game), for the price of 5.94$ each!
Also note the name of the artist on iTunes is Yuzo Korhiso!
Release date does not correspond to anything.. (probably the release date of the game)
Yuzo Koshiro BEST COLLECTION vol.2 have been released on iTunes too, the same way.