what makes you think this is a SMS 1964 Nickel ? First of all a 1964 Special Mint Set is a rarity in it's own right .2nd If by some crazy chance your Nickel was from a SMS it certainly wouldn't look like that one your showing us .
Related to the Families of Lester Merkin Or Eva Adams ? Not a snowballs chance in Hades that is an SMS. Numismatists believe that the 1964 Special Mint Sets may have belonged to former U.S. Mint Director Eva Adams, who was instrumental in bringing the Kennedy half dollar from concept to circulation in just a couple of months after the assassination of President John F. Kennedy on November 22, 1963.
The former Mint director died on August 23, 1991, and her estate was sold soon after. Coin dealer Lester Merkin is known to have bought some if not all of the coins from that sale. ( courtesy Coin World)