I think I've got the right sized 'B', no not the green 'A', I'll check and let you know.
EDIT:- checked, got the 'B', although they are 12.25mm if that'll do. I've got two styles of Luftwaffe lettering in black, rounded and 'squared' corners. I can also let you have the 'A' in black, if you can paint over them?
I'm still searching for a green, or greenish blue 'A' which I think I MIGHT have, but can't promise. Probably got red ones and maybe yellow ones, and also white ones though!