This account is still working, thanks for contacting directly. I just now did the missing flags in traditional style, I hope I haven't forgotten any country (some of them I haven't even heard of).

AH | Austria-Hungary

BL | Saint Barthélemy

CW | Curaçao

GG | Guernsey

IM | Isle of Man

JE | Jersey

LY | Libya

MO | Macau

ND | Northern Ireland

QC | Québec

RH | Rhodesia

SS | South Sudan

SX | Sint Marteen

XK | Kosovo

YU | Yugoslavia