Doesn't look like any Mustang/Cougar shifter I have ever seen. The base size is the same as 65 thru 68, after that they got bigger. Any part numbers on it anywhere? Also with the neutral safety switch in it says to me 69 and newer. Maybe Pinto?
Wasn't Pinto, or Mustang II They didn't have a reverse handle, the shifter alone did that.
The way the handle is made looks like AMC construction maybe?