Me too!!
I wrecked one a couple of weeks ago and when I enquired was told they're not available so I'll watch this thread with interest.
I've found that the uni-bush really protects the arrow from a robin hood - the uni-bush splays out but the shaft (X7 or fatboy) isn't damaged (actually, the X7 gets bent, well the 2 I've done this to were).
If they're not available we'll just have to wait for a side impact ruined shaft.
Simon