There is some contradictory information about that.

Please download the new documentation set (V2).
Here you can find all system exports per country/year.
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SA-75MK Dvina “three van” (SA-2B/F)
Vietnam 1965-16+1*, 1966-18+1*, 1967-42+2*, 1968-4, 1969-2, 1972-12
* means training system

S-75M* Volhov (SA-2E)
Vietnam 1979-8, 1980-3, 1982-3, 1985-4, 1986-8, 1987-10

S-125 Neva (SA-3)
Vietnam 1972-4, 1973-8, 1979-9, 1980-3, 1981-1, 1982-3, 1984-3, 1986-6, 1988-3

Last edited by Hpasp; 07/27/11 08:49 AM.
Hpasp
Free SAM Simulator, "Realistic to the Switch"
(U-2 over Sverdlovsk, B-52's over Hanoi, F-4 Phantoms over the Sinai, F-16's and the F-117A Stealth bomber over the Balkans.)
http://sites.google.com/site/samsimulator1972/home

Book from the author - Soviet Nuclear Weapons in Hungary 1961-1991
https://sites.google.com/view/nuclear-weapons-in-hungary/
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