Customer came in Saturday with a Maadi AK missing the bolt carrier and bolt. Never really messed with one when it comes to working on them. What do I need to know about headspacing them, and where is my best bet for finding the parts?

Thanks for any info/help y'all can offer.

Sourcing a replacement AKM bolt carrier / gas piston unit and bolt won’t be too hard.  Serviceable surplus is still findable (7.62x39 Romanian, Hungarian, Polish etc would all work), and new, unused parts can be had for about $200 give or take.  Unless the replacement bolt happens to headspace correctly, and it probably won’t, you will have to reset the barrel.  Headspacing an AKM like a Maadi means pressing out the barrel pin, pressing the barrel in or out until the headspace is right, then reaming or redrilling the barrel pin channel through the front trunnion hole and pressing a barrel pin back in.  This may mean drilling for and sourcing an oversized barrel pin to account for the barrel’s new position in the trunnion.  There are many threads over on theakforum and akfiles and youtube videos about how to headspace AKs and the tools involved.  Full disclosure - I’m an AK build rookie having only done 3 so far, and I personally wouldn’t be thrilled about doing this on someone else’s rifle as a first AK job.

Thanks for the info. Anyone have any idea of the likelihood of a random bolt head-spacing properly. I'm not working on the gun, just helping the customer find parts. I was afraid the head-spacing was going to be a bit of a pain in the ass, probably more hassle than it is worth.