Various sources mentions rather briefly that the mujaheddin used MILAN ATGMs against the Soviets.
Who supplied these exactly? Were they e.g. from French or UK stocks? And were the US intermediaries for these deliveries, or just the Pakistani and/or Saudis?
Sources consulted:
MILAN missile systems were among the numerous weapons sent to the Mujahideen in Afghanistan in the 1980s by the United States to combat Soviet troops.[9] Wikipedia:Afghanistan
Questionable it was this simple as the MILAN is not made in the US nor acquired by the US Army. Cited source "[9]" is dead link and besides it's a "Small Arms Problem in Central Asia" publication, which I suspect isn't a detailed history anyhow. I've actually managed to locate the publication cited. It says:
The flow of small arms to Afghanistan did not end after the Soviet forces withdrew from the country in February 1989. Just before the withdrawal, the United States increased its arms supplies to Afghanistan to ensure that the Soviet decision to leave would hold. The United States provided the mujaheddin, for example, with Stingers and Milan anti-tank missiles, and continued to support the Afghan guerrillas in their fight against the pro-Soviet Kabul regime headed by President Muhammad Najibullah.
Wikipedia:Operation_Cyclone doesn't mention Milans.
gives as 160 the number of Milan launchers passed to the mujaheddin. The book cited in support (Isby D.C., War in a distant country, Afghanistan : invasion and resistance) isn't more detailed than that. It contains a brief inventory of mujaheddin arsenal, but not how they got them. The book page number cited on Wikipedia is totally off, gives 42, but should be 112, where the book just says
By early 1988, there were reports that the Resistance had received 160 European-designed Milan anti-tank guided missile-launchers, along with training for gunners. These proved effective in action throughout 1988.
And that's all the coverage given to this issue. If the quantity stated in that book is correct, it's a pretty sizable number, comparable e.g. to the official stockpiles of such missiles of some smaller countries (using Wikipedia numbers again).