I have a Square D Homeline box (HOM) and they make those breakers for that: HOM120PCAFI.
I don't know about QO and I don't think that they interchange.
I printed all the HOM info from the Square D pages on the Schneider web pages, so you could go there and look for QO info.
Best of luck.
Press...
Well, I can't post a picture or a link.
So, search Amazon (or Google) for:
"Smooth White Three Gang Wall Plate - Two Toggle Switches One Blank"
and you will come up with another option.
Good luck.