I have both posters for Imperial Armour Volume 5 and 6.
This is what they look like
Volume 5 is just a map of Vraks with an Army listings of
DKOK on the other side.
Here is what Volume 6 Poster looks like with a picture of
DKOK on one side and a map on the other.
I don't have Volume 7 so I can't tell you what the poster looks like.
Hope this helps