Four barrel carburetor for slant 6 Offenhauser manifold?

Do any of you hippies out there have any experience with what four barrel Carburetor works best with the Offenhauser intake manifold? I recently picked up a 61 Lancer that has been sitting over 25 years with this set up with a 4bbl Carter (in which the secondarys are stuck closed) , stock exhaust manifold, unknown engine mods other than MSD electronic ignition. Sounds like it runs great when you pour fuel down the carb. Do you have a carb that you would like to sell? Thanks!