Um, what? The Cokin filter company went out of business? Hmm. I didn't see anything about that on their website:
Welcome to COKIN.COM and Adorama has the normal Cokin filters too. I see the news that Minolta is bailing, but nothing on Cokin. Cokin filters seem to be still on the market.
If not, I also need to look into filling out my line. There may be some more I need/want.