Get the fake wide whitewalls that seat between the tire bead and the edge
of the rim, and keep your modern tires.
I think JCWhitney has them, perhaps other similar accessory suppliers.
Unless you are doing a show car the fakes will serve well for a long
time, maybe outlast more than one set of tires.
Anything from Coker is expensive compared to normal mass produced tires.
Al G.