Howard Blumenthal, 76, of Fort Lee, New Jersey, had faced up to five years in prison.
Seven guns with an estimated value of USD 250,000 to USD 350,000 were seized in December 2012. Among the firearms were a .357 semi-automatic pistol featuring a gold medallion "QS." That's presumed to indicate the late Iraqi president's son, Qusay.
Other guns included two .357 Magnums, a .32-caliber semi-automatic pistol, two 12-gauge shotguns and a semi-automatic, .45-caliber pistol with gold leaf and gold inlays and bearing the initials "QS."
The investigation into the plot began in April 2012, when federal law enforcement officers learned of plans to sell the weapons.
Two other people charged in the case are awaiting trial, while a third has pleaded guilty and is awaiting sentencing.