Borla doesn't sell the mufflers alone. I've tried many times. Your best bet is to watch classifieds and eBay for a used pair. Personally I have given up.
I saw those once in my searches for them and I think they might be them, but I'm not totally sure. I would call and ask if they are the same mufflers as the stingers just to be sure. When I get my tax return those mufflers might be in order