You might also find it at a Surfing Shop like Warm Winds or Gansett Juice in Naragansett. The will also have other wet suit repair products which work on neoprene waders.
You can also find Goop at Job Lot - it's probably gonna be cheaper than West Marine - I think I paid $1.69 for it for my leakables....
"There is no royal road to this heavy surf-fishing. With all the appliances for comfort experience can suggest, there is a certain amount of hard work to be done and exposure to be bourne as a part of the price of success." From "Striped Bass," Scribner's Magazine, 1881.