These may have been rebuilt on an exchange basis. The last slave I bought I took apart and lubed with brake fluid and to check it was put together correctly and didn't have any debris inside This is when I found the shitty RTV seal. (well maybe not RTV but a very flimsy soft floppy gummy bear seal. A Nissan master would be 2 or 3 times that amount.
Yes again, good ball joints are over $50 for good ones.
Recently I bought ball joints from Rockauto - Mevotech for $19 each - not sure why I picked that brand in their daily driver category. They were cheap and did not fit.
Then I ordered Sankei 555 ball joints, made in Japan and they are way better casting and quality - but $55 each.