Doing research on SKS rifles, and I've found that Yugo SKSes are quite common to find in what looks like very good condition, however, most of them are 59/66 with the grenade launcher fitting. I have read that the launcher fitting can leak, causing detrimental malfunction of the rifle. How pertinent is this issue, is it common, and is it easy or a hard thing to solve/fix? How would you fix the leak issue? Would the risk of the GL attachment leaking outweigh buying a very well maintained Yugo SKS? Thanks for any replies.