With 13 inch Tires , there are a Few choices left. I believe that you can ck with Firestone I know they still Offer a 13 inch FR-380 Tire. I kept the Org. Tires on my 1980 Rallye ,they were in nice looking shape still ,and came on the car new. The tire ,as yours were cracking ,and Old 35 years. Happy hunting, there are tires still out there.
