Is it,or was it, registered ETM791? If so, there's a photo of it at my Brock_Fords website at
www.geocities.com/brock_fords/mias.html
That particular Brock Wagon was in a car yard at Eastside Mitsubishi back in 1992. I have more photo's of it if you are interested!
I'm not sure how many wagons were given the Brock treatment, but judging by my knowledge of these cars, I'd say no more than a handful!!
In all, 126 Falcon S/Fairmont Ghias were built and only 5 Brock SEs. Not sure how many Fairlanes or Mavericks, but again probably less than 20 of each!
Good luck with your proposed sale.
Terry