Hi, those are cool speakers.

I tried looking around and in the pics, the tweeters look like Dynaudios, maybe Scanspeak.

Sony lists them as soft dome tweeters. The super tweeter is ceramic, but it doesn't kick in until 22kHz, so I'd say the real tweeting is done by the soft dome.

So, to try and match sound, I'd say to look for a center channel speaker that uses a soft dome tweeter, and try for Dynaudio or Scanspeak drivers. DIY sites like Zalytron and Speaker City may have kits available where you can choose your drivers.

The Sony has a plastic midrange driver, so you could ask about driver matching there, as well.

Sorry to give a vague answer, good luck with this!

You may have luck with the Infinity line, as well, as the treble balance to my ear matches the review of the Sony's as being slightly lean.