Long 45 Degree Flare Nuts for 1928 Chrysler Brake Unions Problem

[leomara]

I've discovered that flare nuts for 1/4 inch and 5/16 inch brake lines only come with one thread size and those thread sizes are too small for the original unions on my car.  The 1/4 line fittings require a 1/2 inch thread and the 5/16 line fittings require a 5/8 inch thread.  All the fittings for 1/4 inch line I've found only come with a 3/8 inch thread and all the fittings for 5/16 inch line only come with a 1/2 inch thread.  Any known sources for the sizes needed? 

Edited February 13, 2021 by leomara (see edit history)

[$um Fun]

Leo, I bought some blanks from Straight Eight for the 5/16 line and tapped the back and may also have  the others you need.  https://straight-eight.com/