The Salvation Army Tune Book (2015) is available in mp3 format as both a full set, and as individual tracks.
The full set of 958 tunes, is available from UK Trade or from www.spstunes.com for approx A$80 + shipping.
Individual tracks are also available from www.spstunes.com for approx A$2 each.
Please note that some users have reported problems when trying to access the SPS Tunes site.