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.
My reverse commuter trike build log: viewtopic.php?t=11384
Fitting glass and weatherstripping: viewtopic.php?f=23&t=6451
Growing various fruit trees, berry bushes, and wine grapes in zone 7b.