Buy a copy of a Chevy magazine, contact one of the 40 companies who advertise SS exhaust parts. Or you could try Burns Stainless, Borla Exhaust or Summit. Or any performance exhaust shop within driving distance to you; they can make what they don't stock.
You really are having trouble finding that part or are you just bored and decided to post here? Just curious; I did a quick Google search and was five pages deep before I found my first useless link. What search terms have you used?