This is one of those odd mystery cars that was made only in the Netherlands. Don't know a whole lot of history on it but the pics are from a Netherlands Mustang site. This car appears to be a barn find and looks to be rare production unit. There is an advert for it but beyond that I don't see a whole lot of press on it or how many were built. 1965 Ford Mustang Country Squire GT. Read the 1966 road test from Car and Driver
There is some claim that it was delivered new as a Mustang GT to Prince Bernhard of the Netherlands. He had it converted to a shooting brake, so he could use it when going hunting. Job was done in the Netherlands by Hollandia sunroofs.
Since they made a handful of these cars I don't know if this is the same car as in the previous photos. The things I noticed besides the color were no trailer hitch and no tailpanel blackout, no side "C" stripe but ... the tag is the same!