Missing a strike plate in a metal/steel frame
Yes, metal frames use machine screws, not self-tapping screws. 

I’d order a plastic “strike box dust cup” too. 

Btw, those existing metal tabs with the screw holes in them are made to be adjusted slightly. I’d be careful moving them, because the screws may not align if you move them too much. However, if the flat head screws do not “seat” properly in the strike plate, you can adjust those tabs.