You've narrowed it down to a small domestic (versus a rebadged import).
A 1986 escort with power brakes has a 19.75mm bore which is .777". The manual version is 21mm if you find your running out of pedal travel.
It has a separate plastic resevoir but it may not be aluminum.
You might try increasing the pedal ratio to use a larger bore with similar effort and travel.
"I want to ride my tricycle. I want to ride my trike."
"I want to ride my tricycle. I want to ride it where I like."https://www.youtube.com/watch?v=Om3C1Ep ... D3E18BB447