There was a good article by Tom Bredehoft about these in All About Glass Vol. 1 No. 1 page 23. They were originally made by Duncan and Miller of Washington, PA circa 1934 and called Old Charlie. When Duncan & Miller closed in 1955 most of their moulds went to the US Glass plant at Tiffin, Ohio but there is no record that this tumbler mould was ever transferred.
The tumblers are being made currently by Appalachian Glass of Weston WV using a mould they acquired from West Virginia Glass Specialty. It is not known how they got the mould. Appalachian Glass call it the Buccaneer.
The whereabouts of the pitcher mould is not known.
All About Glass is the publication of the West Virginia Museum of American Glass. I recommend subscribing to this excellent journal if you don't already. Visit their webpage at:http://wvmag.bglances.com/
SidMod: Link corrected.