You'll want VT-52 for this era.
More like the VT-05. The VT-52 came a few years later. But yeah, the VT-420 is way later.
Fun fact: The VT-52 didn't have a loudspeaker for the bell sound. Instead, it had a electromechanical relay which was set up to self-oscillate.
"Typing a character produced a noise by activating a relay. The relay was also used as a buzzer to sound the bell character, producing a sound that "has been compared to the sound of a '52 Chevy stripping its gears."
YouTube has the sound: https://www.youtube.com/watch?v=bAafRXddfxc
Thanks, I remember it being much louder when I used it in the 80's. Made me jump out of the chair the first time I heard it.
I wrote a VT52 hardware simulation: https://github.com/larsbrinkhoff/terminal-simulator
https://mmastrac.github.io/blaze/
(the API is undocumented but stupidly simple: an async js_read() function and a sync js_write() function)