It is not. However, it has been up for several years with no takers, and I am now prepared to negotiate its purchase rather briskly.
However, that said, unless you are a pure collector and just want to acquire the piece as a pure collector might, remember that six sheets are a challenge.
That said, I have never seen another six on this title. I acquired this in 1986 in Marin County California from a man who had a nice selection of large format posters in better titles of the 1940s and 1950s.
Kirby