I'm in the same boat, Larry, and I'm ordering a complete vent replacement - not just the cap. It's not going to be much work to get the old one off and screw in a new one. Color matching, though...
2005 42' Country Coach Intrigue Ovation LE "Nairobi" #11868, Cat C-13
Him: USAF, Retired
Her: RN, CPC, CPMA, COC
With Skye the mini-Aussie velocimuncher and Maybelle, her ferocious little half-sister