: One of the reasons Russian weaponry is so popular with guerrillas, terrorist group, and insurgents in general, is because thats often all that is available to them. The concept of terrorists spending lots of dough to purchase state-of-the-art equipment is mostly false. After all, why pay thousands of dollars for a brand-new rifle when a used Kalashnikov is so much cheaper. 

Since the end of the Cold War, and even during, Russian weaponry of all kinds was heavily deposited all around the globe, particularly in Africa, the Middle East, Afghanistan, and in the Balkans. Thus, there is no shortage of small arms, light weapons, or ammunition for either, nor will there be in the immediate future. AK-47s, RPKs, RPG-7s, PKMs, and SA-7 MANPADS (Man Portable Air Defense System) are available in large quantities. By far the most common terrorist/guerrilla weapon is the AK-47 assault rifle, which has become synonymous with freedom fighter movements. So too the RPG-7 which has often been dubbed the guerrillas artillery and has seen action everywhere from Angola to Beirut to Lebanon over the past 30 years. Over the years, SA-7s have been known to fall into the wrong hands sometimes. However, quantity aside, the problem with all of this surplus that most of it is either in poor condition, obsolete, or both. If one takes a closer look at the weapons used by Al-Qaeda fighters during Operation Anaconda, one will see that they are primarily armed with AK-47s in terrible condition, firing equally ancient and defective ammunition. The RPG-7s they possess, too, are older models with less powerful warheads. 

 The SA-7, and other, shoulder-fired air defense missiles commonly found in terrorist hands, are completely useless against the countermeasures used in modern aircraft and military helicopters. This gives troops from countries like the US a decided advantage. The cost of such weapons varies from country to country. In Pakistan, for example, an AK-47 rifle can sell for about $500, while an RPG-7 can sell for about $800-1000. In countries like Somalia, however, the going rate for an AK-47 can be as little as $100. In Iraq an RPG-7 can go for about $220, with the rockets costing just $20 to $30 apiece. However, sooner or later, either the supply of weapons is going to corrode into uselessness or insurgent leaders are going to realize the obsolescence of their weapons and go looking for higher quality firepower elsewhere. 

When this happens. In all likelihood, they will again turn to Russia for a number of reasons. The first is that Russia is one of the few countries that is completely self-sufficient, no matter how small their defense budget gets, in weapons of all kinds. Secondly, the weapons they produce are typically suited to the requirements of terrorists or insurgents: cheap, reliable, and rugged while still being high-tech. Finally, availability. Advanced weapon systems, especially small arms and light weapons, can be bought in quantity from corrupt cops or soldiers, stolen from police or interior ministry armories, or purchased from the mind-boggling number of Russian criminal groups that, for all intents, and purposes, own the country. Western countries, especially the US,  tend to keep much better track of where their arms are going. 

Items high on the potential terrorist shopping list would be the latest AK-74s, especially compact shortened versions, sniper rifles, rocket-propelled grenade launchers, SA-18/16 IGLA air defense missiles, and sidearms specially designed to pierce body armor, as well as grenades and explosives. The next generation of unconventional combatants just might be far better armed than the current. 

The thing about obtaining top-quality arms, particularly on the black market, is that it costs more than low-grade weapons. A lot more. When buying top line weapons like advanced shoulder-fired air defense systems and light weapons, the price usual doubles or triples beyond the legal retail price since the weapons themselves are more valuable and there's less of them than older models. Hamas, one of the better armed terrorist groups, has complained that the cost of smuggling weapons has increased dramatically to the point where recently manufactured AK-47s from the Czech Republic are costing about $2,000 each and ammunition is $4 a bullet. Of course, lots of insurgents groups are involved in the black market themselves, often in human trafficking and narcotics, which rakes in more than enough to buy whatever they need. The profits reaped from heroin trafficking in the Balkans are estimated to exceed $400 million, much of which, over the years, has gone to purchase equipment for paramilitaries.