I kept looking at that painting and I had thought I had seen it before. It took me awhile to remember where I saw it and it's in my collection of books. It is ALMOST an exact copy of one that exisit in the Mobile City Museum collection. The difference is the one in the Moble Museum has eleven men driving the propeller, the vessel is longer and the mens feet are touching the deck and their heads are near the overhead, and the Ebay one has cruder details. They both have the same drawing style down to the uniforms and shadowing, you can tell either were both done by the same person with the larger one being a bit better than the other or the smaller Ebay one was crudely copied from the other.
The Mobile Museum states that theirs is titled "C.S.S. Hunley, A fanciful Yankee conjecture".