Actually I haven't much to add, ForestFighter. I paid about £60 posted for my size 3 KZS which I bought for the kecks, as the size 2 jacket was fine. I had to take about 2.5" off the sleeves of the size 3 jacket (others my size may need to remove more as my arms are very long). I had used the size 2 kecks tucked into my boots plenty of times, but they were not as baggy in the legs as they should have been, not just for the look but for comfort - I'm 5'10" 42" chest 38" waist for you to compare, but it took me a fair while to find the size 3 for sale (i got it from seller stalingrad on fleabay - Svetlana doesn't seem to have got much new stock recently but i think she has size 1 and 2 KZS). I have never tried a KLMK onesie, but i suspect the KZS 2 piece is more flexible - it also allows you to use the jacket above afganka kecks, if you can find them, which is an iconic VDV look from the Soviet-Afghan war.
Reportedly the Soviets were using the AK-74 by the time they went into Afghanistan and VDV were definitely issued AKS-74 (side folding skeleton stock / wooden handguards) as standard, but i've seen pictures of Soviet soldiers in Afghan, dressed in M88 Afganka uniform so not a unit low down the pecking order in terms of requisitioning kit (as some units were deployed to Afghan wearing the Syriika uniform which is a variation of the M69 mentioned above), carrying AK-47S (under-folding stock and wooden handguards) - i think vehicle crews maybe, but no doubt they would have faced the same problem we faced when fighting locals carrying AK-47's firing 7.62x39mm: the heavier bullet would have outranged their 5.45mm AK-74 rounds, so who knows, maybe the odd AK-47 was requisitioned for some units/individuals and could be historically accurate...
If you tell me what size you are i'll keep an eye out as i trawl around online, but 1 good place to start looking for Soviet era stuff is redstar-militaria.de - their prices are generally better than the likes of sovietarmystuff.com, soviet-military-form.com, thesovietrussia.com and inside the EU, which is better for tax, shipping costs, and wait times. As has been said, frontoweic.com are also very good. On ebay you might also want to check out valery-seawolf-ru, okudinova for boots and other stuff, and alexcatfish09 has Chechen war stuff as well. There are loads more but i cba finding every fleabayer i've bought from, but as i say, i'll keep an eye out...