Just found this thread. So going back a bit... the only colour Victor periscope box that I ever saw was grey. The pericope was stowed ready for use behind the Nav Radar's seat. The box was only used when the periscope was removed from the aircraft for any reason. I would think that the Vulcan's was the same, as they shared some common components.
So maybe it's a Shack. box. <img src="confused.gif" border="0">