Where to find replacement air filters for my Weber carburetor?

I have a Weber 26/27 carburetor on my 65' 200ci i-6 Mustang. I'm starting to think though that the 26/27 doesn't even exist anymore? Because I can't find a replacement air filter ANYWHERE on the internet, the one I have on right now looks gross but I mean it works and all but its all rusty and not very appealing. The last guy must have not taken good care of it. Unless I'm wrong, but I'm certain that its a 26/27 because it says it on the side of the carburetor.There are no other markings other than "Weber" and "26" on one barrel and "27" on the other barrel. I know it's a DGV series but the closest one that looks the same to it is the 32/36 carburetor, and I don't wanna waste my money buying the wrong air filter. Anyway, anyone know where I could get a plenum to allow the Weber to either accept OEM Mustang air filters or cold air intake filters? Or just help me find another Weber air filter. thanks.