The following guns were used in the movie Gorky Park:
Tokarev TT-33 Pistol
Colt Sako Model L-579 Rifle
In a flashback, Osborne (Lee Marvin) is shown shooting three people at point-blank range with a pistol concealed in a leather bag. The pistol is never seen in the film. In the book, the bag is later recovered from a frozen pond with the pistol inside, which Kirwill (played by Brian Dennehy) identifies as the "Argentine version of the 7.65-mm Mannlicher" with an 8-round magazine. This description is consistent with the Steyr-manufactured Mannlicher Model 1901, which was adopted by Argentina as its army's sidearm; its later descendant was the Mannlicher Model 1905, a slightly larger-framed pistol with a 10-round magazine.
N.B. Steyr's Model 1901 and 1905 pistols were both chambered for the 7.63 Mannlicher cartridge, but in order to distinguish this pistol round from the 7.63 Mauser round, it was referred to in Germany as the 7.65 round, or the 7.63x21.