Aluminum bendix style master
1962-74 Mopar Bendix Style ALUMINUM Master Cylinder
I recall there being a passanger side ported 4 bolt mc on B, C, E, F body cars (don't recall which)
as for interior seepage.
it should not happen if you have good seals and sealing surfaces.
my dart sat for 4 years and seeped fluid onto the front floor, it is still damp but with monthly use it doesn't seep enough to worry about right now.