Many people ask about replacement automotive parts for their sixties and seventies cars. What people have forgotten, or never knew, is that aftermarket (versus OEM GM service parts) are not only no longer available, but the character of the parts has changed driven by the consumer's (that's you) demands.
There was a time when quality was of primary importance. NAPA (founded in 1909 selling parts to fit Ford's Model T car) used to state that they warranted their parts to be as good as, if not better in quality than the factory part; or you got double your money back. NAPA back in the sixties was reselling Moog, Raybestos, or Spicer parts that were all made in America by the same vendors that the factories bought their parts from. Advance Auto Parts was selling the same American made parts from 1934, O'Reilly's since 1957.
It wasn't until Sam Wall got the idea of buying in bulk (ship loads at a time) from China and selling lower quality parts at a discount that the situation in the aftermarket changed. If you got a bad part from Wal-Mart they gave you another one and threw the bad part in the trash. Replacing two or three defective low quality parts was more profitable to Sam than buying one good high quality part. (and Sam got discount when his returns grew too high). Sam also wasn't the one replacing the part: you were, or your mechanic who hated replacing parts for free that was doing the rework on his labor.
Today all I hear are complaints about bad fitting body panels, A-arms with ball joints that fall out when you lower the car off the jack stands, or porous aluminum castings with poor machine work.
I won't eat clams or oysters because muscles (bi-valve animals) are the sewer system of the sea. They eat all of the fish poop and other dendrites that floats to the bottom (including metallic toxins and carcinogenic chemicals). By the same token bottom feeders don't get to complain about the quality of their meals.
If you are buying parts looking for the "best deal" then I have to remind you that you get what you pay for. Unfortunately since every one assumes ball joints cost $3.00 or shocks cost only $10.00 those American manufactures that used to make these parts (Moog, or Monroe or Gabriel) have shuttered their high quality American made parts factories in America because they can not compete on price point.
Today I look for the "Hecho en México" logo for a machine made (CNC or robotic) quality part that has low paid workers that feed the machines and package the parts. For body parts I go used or fiberglass.