Hi David,
Thank you very much for your message. I found a website where they probably sold an original one with a much better print quality and without the "Wehrmachts" stamp on it which was the reason why I believed that it could be fake.
http://www.militaryautographs.com/p...name=Luft%20Arm
There are two additional ones in this photo without the stamp but with a similar print quality:
http://www.xs4all.nl/~robdebie/me163/clothing08.htm
What do you think about these?
Thank you,
Regards,
Roger