Russia, USSR, coin set 1972 with documentation of its order in Moscow by a US citizen

The set includes denominations from 1 Kopeck to 1 Rouble and correspondence regarding the purchase of this set, exchanged between a US citizen and THE BANK FOR FOREIGN TRADE OF THE USSR, which distributes circulation and collector's coins outside the borders of the Soviet Union. A great historical and numismatic curiosity from the Cold War period.