I've done the measurements and thought this was possible, glad to see someone finally make 19.5" wheels with original 8 hand hole centers.
You should be able to use many if not all 19.5" rims you may find, not just from a Dodge, measure the inside diameter of donor rim compared to the outside diameter of you original center. Some machine work may yet be necessary for a good fit.
Look at 8R19.5 tires, also very available and they're taller a little than the original 18" tires and still skinny, they look good and you go faster. They look best on a 6" wide rim, but also fit 6.75" rim if that's what you want to use.