You are smart and you surely know why. Others may not be so here goes....
The pattern isn't the issue, it is the tiny 7/16" BOLTS. The factory built 383 and 440 Darts and Barracudas with these small bolt patterns but they had HUB centric wheels. The hub and lugs were centric together.
The lack of availability of 15" wheels for the small bolt pattern is another issue. You can find 15" stock wheels in the big bolt pattern quite easily. Nobody runs a 13" wheel on a real performance car anymore, do they? Even the availability of a decent 14" tire is limited. I can go right now to local junkyards and find 15" steel wheels to use for a big bolt pattern car.
