I use EDTracker, nice and cheap and does the job. It will work on release as it looks like a mouse to your PC that is then bound to headlook mode, so no need to worry about that. It won't track forward and back head movement like TrackIR, but that's not a problem in ED as you can't use that really anyway.
(Disclosure, Brumster is a mate of mine)
(Disclosure, Brumster is a mate of mine)