Center channel recommendatons for Dahlquist DQ-20

I'm a new guy (actually an oldguy who hasn't been paying attention for 20 years) who doesn't want to have to sell my old friends. I have my old DQ-20s from the 1980's and the only way I'm going to be able to keep them is to use them as mains for the home theater going in the basement rec-room of the new house we are building. I'm hoping to find a reasonably cheap solution for a center channel (less than the Regnar solution of ~$500). My goal is decent 7.1 home theater while maintaining my ability to sneak down there an listen when the kids aren't watching TV.

Thanks!
Mike

p.s. Any reason not to use in-walls for surrounds?