An update on my question about the stickers. Julia Nicolai from PUMA DE (in Germany) researched my question and found that indeed PUMA did use these stickers early in 2000. They were produced by a third party who mistakenly put the space between Rock and well. I received this email from Julia:
Nicolai, Julia <email@example.com
Mon, Jul 8, 3:54 AM (10 days ago)
I found out that this stickers existed in the Puma history.
The knife you have is an original Puma, we sold these ones in the early 2000s.
As far as I know this Rockwell-stickers were made by a foreign supplier who spelled them slightly wrong but they were used anyway.
Later we changed them again, so this is some kind of “special edition”
If you want I can send you new ones.
So, the question is resolved. It was really special for her to do this research and follow up with me. lwbooth