I have a buddy that owns an engine reman facility, he's been complaining that even factory supplied parts now are suspect, nearly all US made quality parts are gone, with so many states jacking up min. wage the market simply could not bear the increase in product cost so they went overseas and bought product that they could sell for an affordable price, then the Chinese manufacturers got into to it as well since they basically gave them the know-how and tooling to make the parts they were buying. Now they compete with the very companies they hired to make those cheaper parts who now make them even cheaper in a race to the bottom only matched buy a ton of outright fraud and counterfeiting.
I just got a headgasket for a Kohler Command the other day, in a factory package that lacks a fire ring around the cylinder. The old gasket had a steel ring to protect the gasket's edge at the cylinder, the new one looks like its cut from gray paper coated with some sort of graphite. Its also thinner than the oem gasket. I've gotten these before but this one is marked CHINA on the gasket. It came from a dealer.
Apparently NGK, Denso, and Bosch plugs are almost 100% counterfeit now, knowing what to look for, I've not been able to find genuine NGK or Bosch plugs for sale anywhere either local or online, Honda branded plugs also are being faked. There are a few videos on identifying suspect spark plugs.
I've found a few that don't even look anything like what they are supposed to be.
I did luck out a few years ago and was able to buy what should be a lifetime supply of NGK, Bosch, and Autolite plugs from an autoparts store that closed down about 30 years ago. The guy shut the business down, then hauled all the parts and shelves home for his own use restoring old cars but he was 81 when he did that. He never touched any of it and I got to clear it all out a few years ago. There was also a good assortment of AC Delco and some Motorcraft in the lot but the majority of them are Autolite and NGK, The place also sold small engine parts and outboard parts which is what got my attention there. He had shut down his business in the late 80's and it sat till 2017. Its great for older engines but not for anything newer if it requires platinum or iridium plugs. Its old enough stock that nearly all of them are still using older numbering systems. Making the older parts book fairly important.