Hello!
While the NH-17's have been dropped from production, there's a large number of them whom are still active. Large being a whole lot.
If you want to play the modern 'neko', you can just go and play a Yamataian and base it on a neko. It's pretty much the same thing, if you read up and it's more recent too.
NH-17's can essentially choose to upgrade to a new NH-22C body, which is, in essence, a Yamataian. They transfer the NH-17's memory, apply the desired comestic changes to the Yamataian body and voila!