1963 brake fluid capacity?

Check the back of your shop manual, it says 0.65 pints... but you are going to need more than that in order to bleed the system... I'd suggest you buy a quart.

When I went online to purchase the brake fluid, Eckler's and Corv.Central both say 2 quarts are requ'd to fill a dry system. At $25 a quart I think I better do a bit more research before ordering- lib

You want to remember that you will also have just a bit softer brake pedal with silicone than you will with the required DOT fluid. Something to consider when you most likely don't have power and they are drum brakes.

It was also brought to my attention by a relative of mine who recently changed his 67 El Camino over to "discs" from "shoes" that he noted a much increased braking power and shorter stopping distance. As I haven't driven the car for nearly 25 years and don't intend (hopefully) to re-discover it's braking limits, I believe I should be able to acclimate myself to the feel of the new brake system. After this long out of the driver's seat, it will probably be like re-starting a relationship with a past love you always hoped to get back together with. Naw, on second thought, I'm sure it will be even better than that- lib

You can likely find brake fluid at a local parts store, some do carry it in stock (I just bought some the other day and they had it in quarts and pints)... ask them if you can return a quart unopened if you don't use it (they have a foil seal glued on the bottle mouth); or, buy a quart and if that isn't enough to complete the bleeding process, go get another quart. Although, I always like to have some extra around the garage for future use.

CC/Eckler's advice is for midyears, and 4-wheel disk brakes have 4x as many wheel cylinders as your car, of larger diameter, plus a larger capacity master cylinder

guess is a quart will do it for your car. Let us know what you find out when you do the job.