Zak's definitely the man when it comes to this sort of thing, but something else to consider would be the 338 Ultra. The extra volume of it will help in regard to noise suppression, and the brake mount is a bit larger than the CB. That said, the suppressor its self is also larger and more expensive than the Ultra 9, as well.
I'm probably being overly cautious, but on my Win Mag-class guns, I use a 338-class can.