Komatsu D21A-7 track fit D21P-7

I am looking at purchasing a D21P-7 with 20 inch swamp pads. I'd like to put the 11.8 inch single grouser pads on it that come standard on the D21A-7. However the Komatsu web site shows the new D21P as having only two options for pads, the 20 inch swamp pads or a 11.8 inch flat pad with a hole in it. I,d like the narrower pad since most of my work will not be in mud ar sand. Thanks