Thank you for making your question to JustAnswer. My name is*****'m an Antiques Expert and I will try to help you with your particular inquiry. Please, don't hesitate to contact me any time or to make follow up questions if needed.
"Gesetzlich geschutzt " is a German expression that means "Protected by law". L Brunner is the name of the print maker, "Schönhauser" is a name of a city in Germany.
Regarding the value of your item, I have just perform a market research of similar sold items as yours. I performed the research based upon the most recent finished auctions and private sells, so the value given is the real market value of your item. This is the only way to know the exact value of your unit.
The value will be in the range of 150-250$.
Please, use the stars to rate my answer or let me know if I can help you any further!
Could you provide a picture of it?
Unfortunately, I could not provide more information of your piece, I could not find anything. Sorry about this. I will opt out the question to see if another expert can come and help you