Will this carb work with a slant six?

You can find aluminum 2bbl intakes on Ram trucks and vans. It's the same thing as a Super six without paying the inflated asking prices from a seller.

The BBD that goes on it is generally fine. You can use a regular 318 BBD and jet it appropriately. You can use a 318 air cleaner as well and simply add your own "Super Six" decal.

You ought to be able to leave the junkyard with everything for well under $100.