As the title said, these are good. Well-made enough, and exactly as described. I wished they were ball bearing load bearing for the posts and wheels, but both are just pins w/o bearings.
So, I guess they're "authentic," but sometimes incorporating new technologies into what's obviously a repair job can make everyone - the repairer and the customer/user - a bit happier. Still, they're good quality, were the best option to fix an old desk chair that others had fixed multiple times, and so I'm good.
The wheel casters were exactly as described. They work perfectly and look good.