1973 United States Mint Proof Set In Original Government Packaging 6 coins. 1973 United States Proof Set 6 coins. The 1973 Proof Set the number of coins is six. The sets now included the Eisenhower Dollar, Kennedy Half Dollar, Washington Quarter, Roosevelt Dime, Jefferson Nickel, and Lincoln Cent. The packaging for the proof set changed starting in 1973. The coins came in a different style plastic holder, with each of the coins sealed in its own separate section. The plastic case had a flip top, which opens and closes to display the coins. The outer box color was now black.