Wineglasses - technical drawing

I am now the proud owner of this drawing by Frank Brangwyn. It's for glasses made by Whitefriars Glasshouse and I love it. I've got enough wineglasses really so here's a new collecting possibility. I'd like to track down one real glass made from these designs, but it is proving really quite difficult - no one seems to know where to find them. Possibly only one set might have been made and it could be languishing in anyone's collection.