spark plug wire plastic holders- 1965???

I have been unable to find the individual plastic- I guess were white, but 45 years old borwn/yellow- that hold the individual plug wires to the valve covers on 1965 273s. Paddock has the 66 and up type that hold 2 wires together. Anyone know a source that has them new?
I couldn't find at R/T Specialities that have a lot of small stuff......
Thanks in advance, Gib