Just came across my old Identity Card. Buff coloured card, 3 1/2 inches by 5 inches (so if it was opened up it'd be 7 inches by 5 inches).

On the front at box made of three lines drawn 3/8 inches away from the edge. Inside the box, in capital,letters "NATIONAL: REGISTRATION" (on two lines), with a crest below of the Lion and the Unicorn holding the crown with the royal coat of arms. Below that, in larger capital letters IDENTITY CARD (again on two lines). (Mines also got UNDER SIXTEEN YEARS - in case you think I'm a contemporary of Captain Mainwaring...)

Inside there are boxes for number and name and address and an official stamp (like a postmark), and room for three change of addresses - all of which would have to be registered with the local National Registration Office.

I hope this helps - if a photocopy would be of any use, just let me know. Though I think you've already got more than you want. (I'd have put this on a personal message to Don Meixner, but for some reason it couldn't find that name, with or without the gap.