No offense, but I've heard that the Cross Fire is best used as a boat anchor. If originality is not a concern, I might consider selling the engine to someone who needs an original engine for a restoration, and then buying a crate engine with the advertised hp you're looking for. The intake and heads on the Cross Fire are so restrictive that you'll have to replace them to get good power, which means you are no longer original.
But, if you still want to do a cam swap, one of the cam marketers like Energy could probably recommend one.