Taken from: https://www.the-northrop-f-5-enthusiast-page.info/AirForces/VietnamNorthAF.html
Original creator of the aircraft body is not me but I couldn't find the creator.
Missiles from Rambo Missile Pack 1.1 by RamboJutter:
https://www.simpleplanes.com/a/NAnCFA/Rambo-Missile-Pack-1-1
The Socialist Republic of Vietnam (North Vietnam) "inherited" 87 Northrop F-5A Freedom Fighters and 27 F-5E Tigers after the collaps of the Republic of Vietam (South Vietnam) end April 1975; some were
operational, others not, due to lack of spares or in maintenance. Immediate flyable were 41 Northrop F-5s, especially at Tan Son Nhut AB

Unofficial sources state that circa 60 Northrop F-5As (at least 2 F-5B, 9 RF-5A) and 27 F-5Es were abandoned by South Vietnam; it was extremely difficult to be used by the new Air Force because there
were insufficent spare parts and records for the aircrafts; pilots and ground crew were only fluent in Russian language and procedures. Of help were former South Vietnamese personnel who joined the North
Vietnamese Air Force, though it is not clear if true and how many.