Redekop and a couple of others made straw choppers in Canada for various combines including CIH. The Redekop processes both the straw and the chaff, and it may the same as the chopper used on the Deere STS machines or very similar. The Redekop site is not up and running yet, but I am sure you can find a phone number by checking a directory search site for Saskatchewan. There was other ones called the Straw storm and Urvold, but that is about all I know about them.