I can however make an educated guess and say that (the Chinese being Chinese) probably had "rat holed" several thousand receivers during the run of rifles for the PRC forces. Again, the Chinese being who they are, given an opportunity to make hard cash from us "round eyes," they used them up at the first opportunity.
Same goes for any other parts. They learned through the years that there is no economy in "rat holing" obsolete parts or firearms, so they dump them now given the chance.
eb


