it's not east of the river nile, it's called "harvest in the east" by tommy mccook, though it was mislabeled as a version of east of the river nile on some questionably licensed augustus pablo compilation (same question bothered me for like a year).

Does anyone happen to have an mp3 of this? Zomby gave it away on twitter but it seems to have disappeared from the internet, one of his best tunes imo.