Boeing Clipper history

Rico says his friend Tex forwards this about his late father-in-law:

This is the aircraft that Candy's father, John Madigan, flew during the war; a new young pilot from Minnesota, he was assigned to fly Boeing Clippers out of San Francisco's Treasure Island. John was assigned to the Pan American AVG, the same group of pilots that flew the Flying Tigers in China during World War Two, before the US had declared war on Japan or Germany. He knew and trained under famous pilots as General Doolittle and also met Charles Lindbergh. Did his training at Randolph Field in San Antonio, which was the main training facility for the Army Air Corps and some Navy air training as well. As a AVG pilot, he would ferry such well-known officers as Admirals Nimitz, Halsey, and many others on flights between San Francisco and Pearl Harbor in Hawaii. He had some great stories to share.
John would later be awarded three service awards from the United States Air Force at Randolph AFB in Texas on 11 August 1996 for his services, due in great part to Candy's work on getting VA assistantance for her Dad.
John later met his future wife Hyldia, Candy's mom, while on leave, having coffee at one of the many coffee lunch counters that dotted the San Francisco scene. Hyldia was a cute little lady from Providence, Rhode Island, in California to find her life's goal as a songwriter for move studios.
I believe that Boeing only built fourteen of these pre-war gentle giants for Pan Am.  I don’t believe that a single one survived or was preserved.  I believe that one was shot up and sank by the Japanese in Hong Kong Harbor at the outset of the war on 8 December 1941, but I am not sure about the ultimate disposition of the other thirteen.