1962-64 409 & 425HP (2 X 4) Carter AFB 3361S Front
http://www.348-409.com/part.html#CN
It looks like they are worth more as Chevy carbs. Everything I saw on that part number showed a 409 useage. WCFB was cast iron as I recall, or mostly cast iron. It supposedly stood for Will Carter Four Barrel. $.02.