John,
Chevy used a Rochester 4GC (4-jet)in that era (55-59). The problem is that the car restorers have just about dried up the supply of 4 jets & WCFB's for stock applications. I have seen them in the Classic Chevy Magazine for up to $500. It might be easier to find an aftermarket aluminum manifold and a Carter AFB, Elelbrock, or Holly carb(Preferably under 500CFM). Probably less expensive also. Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine