looking for carter carbs for 2x4 set up 400cfm

hey, thanks for responding guys........yeah, i already have the manifold, holly's won't fit on it, it's an edelbrock 318 that will be port matched, dual plane under the hood deal. i know those 9400 series are hard to find, i see a few on e-bay every once in a while, there always pricey, so i figured i'd look around here and see if anyone has anything. my next option would be a couple of 500's.