I just purchased a 2000 ws6. I was checking ls1sounds.com and found the slp dual dual which is part number 31029. It looks like this part cannot be found anymore. So I’m hoping maybe someone somewhere has this lying around in a dusty warehouse somewhere and wants to sell it. The new replacement 31083 sounds horrible.

 

Any Firehawk, and the SLP optioned SS's had them. Your best bet would be buying a used cat-back.

Finding one brand new will take you a while.