Walker. Also put in a new float; the 1920 uses a nitrophyll foam float that takes on fuel and gets heavier than it's supposed to be over the years. See here.
That'll come as a surprise to those who've been steadily buying-down my stash of new (not remanufactured or rebuilt) slant-6 carburetors. ;-) You're right there are none presently being manufactured, but there are still some NOS units floating around.