This model was not marketed by Parker so it is seldom seen and most pen collectors don't know it exists. Notice in the picture the nib on the fountain pen lacks the familiar Parker name, 14K gold content and country of origin. Also the chrome section ring lacks the normal ruled lines.
My guess is this piece would have been used by the pen dealers sometime in the late 1960s or early 1970s, based on the triangular grip section, if it was actually sold. Here is a link to the prototype owned by a collector.