This is an O-27 flat car. I think it was offered by Train Buddies. It was apparently offered at York. I saw it on the internet with this explanation:
NOW FOR 2013 - Da Artist has again been inspired by the largest of mammals and has produced a new version/variation of the Shamu Submarine Flat. On display at Spring York 2013 was the SHAMU SUBMARINE on SEAWORLD ORLANDO Flatcar. And for sub collectors there are other differences that make this car a bookend must along with the year end 2002 version. The new 2013 version of the SHAMU submarine is on a SeaWorld ORLANDO Flatcar. The flat is a different shade of blue. Instead of 3831 the flat has crisp reporting numbers to the left of SeaWorld. The Submarine has the Shamu logo centered on the side of the Orca whale paint. For 2013 the black paint is more matt compared to 2002 and the conning tower is black with no lettering (to assist with more stealth surfacing in the waters off Florida). And, the ORLANDO flat rides on die cast sprung trucks. When you view the train car after it passes on your tracks you will surely agree that this is a WHALE OF A TAIL (tale) 2013 addition to the fleet. Visit Trainbuddies and Search =SHAMU= The new fleet is even smaller than 10 years ago. We have only THREE CARS in our harbor. Act quickly - before the fleet submerges again (probably for the final voyage!) - DIVE-DIVE!
Anyone see it at York or have one? Just curious. Matt