I am pleased to announce that the stereo version is now available! For smaller file size and therefore faster upload/download speed, I converted the track into a FLAC using maximum compression, and then split it into a six-part RAR.
My AC3 encoder needs wav files to work from, so keep that in mind if you want to go that route. A high-bitrate AC3 will offer much of the sound quality of PCM while allowing more disc space and bandwidth for the video, though you are welcome to use the uncompressed audio directly if you wish. For best results, avoid using any dynamic range compression settings and do not adjust the dialnorm (it should be left at -31).
Part one: http://www.sendspace.com/file/efonsr
Part two: http://www.sendspace.com/file/c62qjm
Part three: http://www.sendspace.com/file/iqwit0
Part four: http://www.sendspace.com/file/rk7p55
Part five: http://www.sendspace.com/file/iypdet
Part six: http://www.sendspace.com/file/q5g9be
While the stereo version sounds excellent, if you have the proper setup you should definitely be on the lookout for the 5.1 version, in order to take advantage of the extra bass content--an important part of the 70mm experience. It should hopefully be available soon.