For sale today is a Polish 1960s model AK-47 parts kit. These things are pretty neat. You  don't see these too often. The switch on the gas block was for shutting the gas block off to shoot grenades this was a Grenadier rifle so if he was in combat, he can switch off the gas and use it to launch grenades. Then if he wasn't launch grandes he was a rifleman. The condition of the kit is battlefield Pick Up. Has has rust and dings, but should clean up. They can turn out real nice when they're cleaned up and built up by A competent gunsmith that knows what they're doing. This kit is  just piece of history and I believe the date on it is 1969 this is a milled rifle. You do need a new barrel and a new milled receiver. Amongst other parts, maybe a new trigger and a few other things a gunsmith would know what you need. If you don't know what a milled AK is, please feel free to Google it.  The first $600 in my hand takes it. Best if you text me I really never pick up my phone