The stamps to which you refer can be found listed in the Michel Specialised Band I. Indicated by PFä in italic under their respective issues.
They are for the most part exceptionally rare.
From time to time articles appear in Philatelie.
Die Postfälschungen des Deutschen Kaiserreichs, Jaschke-Lantelme, has illustrations of all of the forgeries. I believe this is still available from the author. His address can be found at;
However to provide illustrations from either of the above mentioned publications would be a severe infringement of copyright law.
There may be a very slim chance that the forum members have some of the forgeries in their possession, in which case, they may choose to upload them.
