I found --and purchased-- these awesome Plymouth Duster Wheel Covers ( 1972-1976 ) from Shapeways ! 100% perfect for my 1973 Duster build (going to make this build as close as possible to my 1:1 Duster which I owned back in 1992) .
https://www.shapeways.com/product/UNPLAS5SQ/1971-plymouth-hubcaps?optionId=97877897&li=shops