There is an old joke that says that many governments used to or still do pay out the nose for toys and machinery made in their native land as opposed to just going out and saving money by buying something that is readily available that was made somewhere's else, like just across the channel or the border...
The AK-47 at it's worst, is a rough piece of junk that will fire but not too well or too often. The AK-47 at it's best, is a jewel-like work of art, the epitome of fit, finish, plastic work and accuracy. Hell, even the bayonets are cute.
It is almost ubuiquitous in the world outside middle Europe.
You can find the damn thing, and it's younger cousin, the AKM, in the thousands in practically every country in South America, Asia, Africa, the Middle East, the Pacific Rim and, of course, the former Soviet Union and some obscure place called Cuba. They can be found in Jamaica, the Philippines, and Sri Lanka.
There are perhaps more AK-47s and their derivatives in existence than any other modern weapon, except possibly the Armalite family of rifles or the H and K G3. I don't think the FN FALS even count, as they were made for such a short period, but I could be wrong. At one point in history, a million or two of American M1 carbines and M1 Garands were found in various jungles and friendly dictatorships, and the bolt action Mausers and SMLEs were fairly easy to find all over the world, but the AK-47 is the microwave of military cooking. It's short, simple to operate, and it only has a few levers and switches.
There are so many of them around, floating free in individual hands or piled up in warehouses, that you could stop manufacturing them and still have enough on hand to supply every army for the next hundred years. There are even AKS made by hand in local smithys in some practical parts of the world.
There were so many of them available during the Vietnam conflict that the U.S. military could have given up on bringing their own weapons and just used what was at hand and saved all kinds money on ammo and training... and so forth. They shipped so many captured weapons home that they could have used them to supply their allies for the next forty years and who's to say that they didn't?
There were some US soldiers who dropped their M16s in the mud that helped jam them and picked up AKs from the NVA and used them. When the "elite" forces when into Afghanistan recently, dressed in mufti and associating with the locals, they took their own sanitized AKs with them.
The Britich military could have saved billions in funds if they'd just adopted the AK family and not goofed around with the bullpup montrosities they've saddled their troops with for the last twenty years.
The US has lost thousands of AKs that they supplied to their friends in Afghanistan and Iraq. What's truly funny is that many of those carbines were bought brand new instead of dug out of the backstock. What's even funnier is that Iraq was a nation of rifle owners before the US moved in and established martial law and decided to disarm the law-abiding populace which now has to learn to defend itself with towels...
The Israelis knew a good thing when they saw it and a General named Galil took the Valmet version of the AK's upper receiver and essentially mated it to an M16 lower receiver and got the best of both worlds as he saw it, an AK that would take the M16 round and the M16 magazine. I'm not a big fan of the 5.56mm round, but it did extend the range of the weapon without adding a lot of recoil. The Galils and the Valmet AK-based weapons are pretty to look at and incorporated some very modern features, particularly that cute bottle opener and wire cutter incorporated into the integral bipod on the Galil.
I don't really like the AK enough to own one. I'd much rather have one of the older Swiss models, in 7.5, like the STG 57 or the AMT, just because they are so cool to look at and so well-built. But the point is that there are so many of them that no government should ever have to buy a new rifle or carbine or even submachine gun ever again. There are enough AKs floating around to arm every standing army in the world and a few sitting ones.