If you can find a base, use this
https://www2.wixfilters.com/Lookup/FilterBySize.aspx to find a paper filter in the size you want. Most of the listing have the CFM capabilities of the filter. The smaller filters don't move much air, so keep that in mind.
The metal mesh is less restrictive than paper if cleaned and oiled correctly, I used some perforated aluminum sheeting cut to size wrapped around my paper filter to give it more of old time filter look to hide the modern paper look. A copper or brass mesh would look good also.
To see a really bad idea, look up the filters for the 2" or 3" diameter filters you see on a lot of the " custom cars ", you know the little helmet type filters with a few slots in them, they are for single cylinder lawn mowers!
