I would have to agree with the others that a Goodyear Wide Tread is the way to go if you want showroom correct and don't want to hunt down period Firestones.
The picture of your car with the dent is definitely the later version of a wide tread based on the size of the word Wide and how far around the tire the Wide O Oval stretches.
See the repro version on my COPO, right picture,which should also have the 1969 version tire which says Wide Oval F70-14 in smaller type, left picture (unfortunately not reproduced). If you want to recreate the car back at the honeymoon period the repro Wide Oval would fit the bill, just don't recreate the dent just for the sake of period correctness!
