The Mogamis, too. Look at pictures. A single SeaRam on top of the hangar, at the moment, though more weapons will be fitted later.Yeh, the Izumos are Searam. So could be for those. I thought that those were already fitted with previous ordered stuff. But maybe not, and maybe the want to slowly increase their reload stockpile. With the Izumos, they may have reloads on ship like the Americans do.
https://upload.wikimedia.org/wikipedia/commons/3/3c/海上自衛隊_護衛艦もがみ_FFM-1.3.jpg