Or you could hunt the wrecking yards or battery recycle yards for the period correct old battery.
Then do what I did.
Cut the bottom and back out of the old battery. Gut it of the cells (the acid would have had to be drained and the battery flushed/neutralized first).
Detail the battery case. Get the correct battery caps (if it doesn't have them) which are available on the aftermarket.
Then the old Autolite StaFul battery case slips right over a modern Optima battery.
Like this:
Cheers
Greg