1b carburetor on my slant 6

Does anyone know where I can get a 1 barrel carburetor for my 71 slant 6 duster ? I plan on only running the engine for maybe another year I seen the classic industries is out of stock. I do have a quad intake setup but I really don't want to run it due to the fact that I'm just going to swap it out to a 340 that I'm currently rebuilding ... Anyone sell them new ?