Hey I remember the Timewindow great sounding speaker and suprising bass response. Try to find if DCM has a web page. Most equiptment Manufacturers have owners manuals as pdf's that you can download of old products.

In my area (philadelphia) we have a place in Bryn Mywr PA that rebuilds speakers. They replace the surrounds, cones, voice coil ,what ever you need to original specs. They do incredable work. There must be someone in your area to do the same. Ask at your local high end stereo store, they will probably know someone. If you live near Philadelphia its called Soundex. Its on Lancaster ave in Bryn Mywr PA.