Leo called it. That is the modern radial size closest to the original bias ply size. They're 30+ or so inches in diameter so you'll be able to travel down the highway faster at lower engine rpm.
The good thing is there are plenty of different brands to choose from on Amazon for about $100 each.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
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