Some people look for the center console subwoofer insert. Here is one in NY.
https://hudsonvalley.craigslist.org/pts/d/kingston-tj-wrangler-console-97-05/7518524949.html
https://hudsonvalley.craigslist.org/pts/d/kingston-tj-wrangler-console-97-05/7518524949.html