My limited experience with buying vintage chips out of China is that if you really need it, place multiple orders and expect to get half the orders for free when the parts sold as NOS or unmolested pulls show up clearly solder dipped and/or remarked, in very not ESD safe packaging, nonfunctional, etc. I've gotten stuff that was NOS the best I could tell, in chip tubes, and I've gotten stuff that claimed NOS but showed up as solder dipped with mixed date codes, stacked up and wrapped in cling wrap. To be fair those chips do seem to work, but still, not cool.
Ebay, or at least Ali with paypal, is preferred if you don't like throwing money away.