I know that a Redrum device is capable of handling 10 percussion instruments, but I was wondering whether it is possible to add a couple more?

My friend programmed a messy drum track in Sonar with EZ Drummer that I would like to learn to play on the drums. I want to program it into Reason to be able to see it better, but I need at least 12-14 percussion instruments and it appears that Redrum can only handle 10.

I know I could just add a second Redrum device but then I loose the advantage of seeing everything on one screen (I might as well just stick with Sonar in that case). Is there a way to add a few more percussion instruments to a Redrum device, and if not, is there another device that can help me out?