NAPA 6301075 works. It is a little thicker so the PCV hangs only 1/16" or so below the grommet inside the rocker box.
Napa shows that one specs at:
PCV Valve Grommet I.D. 0.7 in.
PCV Valve Grommet O.D. 1.501 in.
PCV Valve Grommet Thickness 0.705 in.
So it's larger than the 1.22"
My Cal custom has a 1" hole. I might have to have it machined open a little?
Looking at the profile shot of this grommet on the Napa site I will just grab one on the way home tomorrow to measure/check
https://www.napaonline.com/en/p/NDP6301075