There were some rumours about that making rounds in the internet while ago, but I don't think it's true. There's still plenty of Compomotive wheels for sale as new and their website is still up. I asked Compomotive directly about their CXN wheels, and they said that the split wheels and their parts are no longer continued, so no way of getting spare parts/wheels new anymore. I guess they used to make these wheels and spare parts around five years ago, but not anymore.

So if someone happens to have one centre cap for 16-17'' CXNs lying around I would be interested...