where to buy grease/dust caps for 11.75" rotors?

I found these on Ebay. Says they will fit the 1977 Cordoba. On the Dorman site it also list all the applications this part is on and it is LOOONG. I know the thread is a few months old but what the heck blame it on the new guy. I am doing the 11.75" rotor Wilwood caliper swap on my '67 Formula S and this was the part stressing me the most.

DORMAN 13996 Wheel Dust Cap