Can be purchased from Beatport and iTunes as part of the Ninja Tune XX compilation ('Volume 2', in this case), but not as an individual track. It's right down on page 4 there on Beatport in 'album only' mode, probably because they don't want to sell a 16 minute track for £1.30. Tight gits.
Talking of tight, it's nigh on £16 on there and a tenner on iTunes.
You can hear a sample of it there too. It sounds really fucking weird. And surprisingly funky. Imagine Chile Of The Bass Generation stuck through a blender.