Need a center channel speake for KEF 107 surrounds

McIntosh 134 Processor
McIntosh 841 CD/DVD
McIntosh 7010 LD
McIntosh 7083 Tuner
McIntosh 2300 Amp (2)
McIntosh 2100 Amp (3)
Velodyne ULD Series II (18 in. I think)
Pioneer PDF27 (2)
KEF 107s (3pr)
I recently popped for the 134. Before this purchase (spensive toy) I was using two of the 107s as a center channel. Now, I can go to 7.1 and have the stuff to do it if I use the 107s as fronts, surrounds and rear surrounds. So, to continue the game, I need a center speaker. I am in too deep to consider changing out the 107s and buying surround speakers. The question is what would sound good as a center with the with the 107s. Recall, 107s are pre Uni-Q. In fact, I don't know if KEF made any surround stuff at all at the time 107s were being made.