This word does not appear in The Official Scrabble Players Dictionary (in the vicinity of irate and ire, which is how I was thinking about it). I thought I made it up.
When I looked for it in my Compact Edition OED, I found iredy, an obsolete word that means ready, prepared, viz., c1300 Beket 766 Iredi ich am the deth to afonge.
Online it's a different story (because of course I don't have all 20 volumes of this dictionary). There it was. And it turns out, it is quite a ways from ire and irate.
Irey (with variant spelling irie) means: Great, fine, all right; pleasing to the senses; powerful.
1978 Gleaner (Kingston, Jamaica) 16 July 23/9 Horace wasn't prepared to leave his wife for Ruby, but...the idea of another woman on the side was both irey and roots.