It's an aftermarket radio that dealers would install.
I ordered my first five Fords (1964 thru 79) without radios and bought the radio from an electronics store.
Guess it saved a couple bucks to order a car without a radio and then install the aftermarket kit.
The prices were usually half of the factory radio price, $24.95, an antenna was about $5.
They are period-correct, but just not factory-correct.
The radios I bought were Philco or Motorola without any visible identification.
There was an instruction sheet and as "do-it-myself" type, installation was a breeze. I wished I held on to the radio delete panel.
Jim