I've had those and they are excellent performers. The easiest thing to do is to just get another single CA1 and use it for the center channel.
Alternatively, if you could find a pair of CA2's, go for those (you'll be pleased!) and then use one of your CA1's for the center.
Good luck!
Alternatively, if you could find a pair of CA2's, go for those (you'll be pleased!) and then use one of your CA1's for the center.
Good luck!