Stu (see comment below) has identified this boat as "the former Coast Guard lifeboat that rescued the crew of the tanker Pendleton under impossible conditions back in the early 50's. Look it up, its an incredible story. The boat's been fully restored."
It really is an incredible story. To read it click Here: http://www.uscg.mil/history/articles/pendleton_webster.asp
Thanks Stu.