One should only accept a RZM tagged Zeltbahn as a HJ Zeltbahn. http://www.hj-research.com/forum/f38/hj-zeltbahn-91/
There are several threads in the equipment section on different Zeltbahnen found somewhere.
Most have some kind of stamps or writing, but no RZM tag
One might say that a Zeltbahn was maybe used by the HJ, or this kind of Zeltbahn was used by the HJ.
But to call it a HJ Zeltbahn you need the RZM tag. Any accompanying story is not good enough.