I don't think you are going to find anyone just selling the base new. I'm almost sure the MW has a small air cleaner element and base.

You may find someone that put the Ford Motorsport drop base on their unsilenced air cleaner and wants to sell thier old base. IMHO, that's the best bet.

Or, I think you could just take a single snorkle 4bbl air cleaner that takes the same air cleaner element and... everything off but the base.