Some additional links to check:

Coast Guard Historian's Office:
http://www.uscg.mil/hq/g-cp/history/collect.html

National Lightship Trust:
http://www.lightship-trust.org/

Not sure if this is a 'sister ship', but the "Buffalo" stationed in Lake Erie is portrayed by marine artist Jim Clary at:
http://www.jclary.com/lightship82.html

Not related, but one that's interesting is this sonargram of the sunken Lightship Vinyard Sound off the coast of Massachusetts:
http://www.kleinsonar.com/image/sw_vinls.html

Good luck.