Here is the adjustable gas piston. https://www.theoutdoorstrader.com/threads/user-adjustable-piston-for-ak-run-a-can-easier.1472131/
One new adjustable gas block here: http://www.thefirearmblog.com/blog/2017/08/15/dead-goose-society/amp/
And this one is from Definitive Arms
One new adjustable gas block here: http://www.thefirearmblog.com/blog/2017/08/15/dead-goose-society/amp/
And this one is from Definitive Arms