^Yup. I had a yellow one with coaster brake, looked just like that, I guess I got it in '73.
The two brakes and various Sturmey Archer clues suggest it's a three speed with the indicator, cable and shifter all missing. Not hard to replace.
That's what I'm thinking.
I'm guessing this is a 22" frame, so if the seller emails me back, I may go look at it tonight.