Made in either the GM Romulus or Tonawanda engine plant. Same plants that supply GM trucks.
Why spend $130 for a used piston and con rod on ebay when new from GM its about $60
For $800 you can get new rotating kits with better pistons and forged rods, or for $300 you can get a pull out motor from LKQ
You just cant take a piston from one motor and drop it into the bore of another motor and hope it to work. You need to measure, at least hone, and install new rings