Those are pre-facelift k10 rims which were standard on all micras of that era in all parts of the world, and they are most definately 12inch. They will not fit the facelift k10 as the facelift has larger front break disks, that's why they upped the size to 13inch. If you want to fit the pre-facelift grill then you will also need to fit the pre-facelift headlights and bonnet as they are different shapes and sizes and don't go together without moddification.
Best thing to do with you faded grill is to t-cut it (best done off the car if you can), then polish it and it'll come up like new. I've done this with three grills now, 2 reds & 1 blue.