I got a quote for 2420A081XB "PANEL,A/T SHIFT INDICA" at a local Mitsubishi dealer for 107€. Ouch. Mitsubishi has one in Holland. Couple of days to deliver. Pretty pricey. I'll have to think about this and/or look for a used part. It might have Eco and B instead of B and C, but still much prettier than no cover.
Btw, I tried all the three forward gears on the C-Zero now. I set the red needle on Eco and shifted "gears" D-B-C. No change in power felt or any movement on the needle. Funny that they'd go through the trouble of designing B and C gears specifically into these PSA vehicles, in different order, naming and characteristics, but then decide to leave them out completely. Or do the European i-MiEVs have PRNDBC as well? I found a picture of a panel with those markings:https://www.dropbox.com/s/gfzz1w203enbysk/0522.jpg?dl=0
I've really missed a low regen "C" position and actually it has been there all along. Oh well, I suppose it's better now than never.