I have no knowledge beyond what's on the Borrani site - they're listing wire wheels for modern cars at up to 20 inches.
In the mail Borrani sent me on 07.07.2015 they clearly stated that for the Morgan Aero it was possible to have them only with 18 inches "We cannot produce 19 inches. Car has passed test with 18 only" (in Italian:
mi spiace ma non possiamo produrli da 19”, la vettura ha passato i test con i 18”).
I hope for PeterJ things may have changes in the last four years.
