Westinghouse disposer....
Late fifties to early sixties at oldest.
By the latter sixties they had been cheapeded considerably, as the Westinghouse Appliance Co. was becoming less profitable. My family had a 1967 Westinghouse disposer. By this time the hopper had been reduced in size, the exterior had a totally hard plastic shell and very minimal sound insulation. The turntable and impellers both redesigned from what you see in the picture.
The 1967 Westinghouse, along with the Whirlpool "Bone Specialist" disposals were rated at the very bottom of the Consumer Report ratings.
The only thing below the Westinghouse was the Tappan, rated "unacceptable," due to it's totally clogging on Consumer Reports' corn husk grinding test.
I suspect this unit would be a very decent machine. I would certainly purchase it if the mounting collar/flange were available.