225 Slant Six Air Cleaner

Hey all, I'm new to the forum but have been searching and using it for about 2 years now.

I have a 1974 Dart Swinger with a 225 slant 6 that is complete and original with less than 90k miles on it. (Original owner passed in '97, I bought it from the grandson who never transfered the ownership) I've gone through the front end (ball joints, tie rods, wheel bearings, brakes(disc in front) shocks etc) as well as the rear drum brake assemblies.
I've been working on all of my own vehicles for 20+ years, have owned and worked on multiple makes and models of older and newer vehicles and have a fundamental understanding of mechanics.

The only thing I have come across so far that is stumping me is a missing top of the air cleaner assembly. I'm not adverse to aftermarket or reproduction. I would like to keep this car as close to original as possible with as straight and clean as it is. Any help or insight is appreciated.