Funny how quite a bit of
IRS stuff has been released only recently, like the Superpro strut top mounts and even the Shockworks coil overs. Must be a bit of demand out there.
This thread suggests 235,990 total AUs built, with 11,742 XR models that would have come with
IRS standard (except that includes utes). Add
746 FTEs, 12,439 Fairlanes and LTDs (according to
Wikipedia), and that's at least 25,000 cars.
But you have to minus utes from the XR numbers and add Fairmont Ghias and any examples that got the optional
IRS. So who knows.