For now, but the network that owns it notified the creator that they have plans to let Netflix's license expire, and then not license it elsewhere: https://news.ycombinator.com/item?id=33012167
That's probably exactly why it's no longer available on amazon.
I wouldn't be surprised if the OP's content was pulled because amazon lost access to the license.
How is that relevant?
Just curious why would anyone want to buy it.
He paid $5 a season. Assuming he doesn't want to watch anything else on Netflix, it's better to just buy it outright.