After reading the following information from Steinmarks, I would make the guess that it was offered for sale between 1910-11 and 1917. I would base those dates on the assumption that German steins were not a popular item in America after a Declaration of War was passed.
Steinzeugwerke Höhr-Grenzhausen GmbH
Höhr & Grenzhausen, Hesse-Nassau, Prussia. (now Höhr-Grenzhausen, Rhineland Palatinate).
A sales consortium, created and directed by Paul Merkelbach in 1910/1911, consisting of Simon Peter Gerz I, Reinhold Hanke, Reinhold Merkelbach & Walter Müller.
Walter Müller is not known to have supplied any product via Steinzeugwerke, due to the parlous state of his finances. It is known that he had left the organisation by the
19th January 1912, since this was the publication date of the first Steinzeugwerke catalogue, in which he did not figure.
It has been reported that Reinhold Hanke left the consortium in 1913, leaving only Simon Peter Gerz I and Reinhold Merkelbach. Reinhold Merkelbach’s kilns were at their best producing the "Kölnisch Braun" products, as well as "Braun Geflammte" finishes, whereas the kilns of Simon Peter Gerz I were better suited for the "Blue-Gray" saltglazed finishes. Then Simon Peter Gerz I quit in 1918, leaving only Reinhold Merkelbach with the Steinzeugwerke company. The moulds that had been used by three of the four original contributors stayed with Steinzeugwerke, and effectively became the possession of the firm of Reinhold Merkelbach. It is doubtful whether Walter Müller’s moulds were included in this collection, since nothing was ever produced from them. Walter Müller’s assets were sold to Steinzeug-Industrie G.m.b.H. before 1918. Steinzeugwerke ceased operating in 1921, and was wound up in 1936.