Sea Rescue (7601) was released in 1964 without the addition of the life vest, which was added in 1966. The set is virtually identical to the Pilot's Survival set. The vest was available on and individual card as well. The use of the same items in various sets is indicative of both Hasbro's thriftiness and the challenge of quickly manufacturing enough stock to fill the larger than expected orders in the first year. Below, the first release version, available in 1964 and 1965.
The version below was available in 1966 and 1967, with the addition of a life vest.