Where can i get an 04 cadillac cts catalytic converter?

I was told that it was a factory item and I could only get it at a cadillac dealership. That would cost around 900 dollars and i don't want to spend that much.Where can i get an 04 cadillac cts catalytic converter?Shark, Left or right bank? Cat is part of exhaust manifold. Try Brock Auto Parts on-line. No emission warranty on your 04 cad? GM part only. Good Luck TWWhere can i get an 04 cadillac cts catalytic converter? Well someone Im sure makes one you just have to look around online or.... find someone to install a universal converter and weld it in place might be half the price.Where can i get an 04 cadillac cts catalytic converter?have you tried Grieg's list? not sure of spelling for Grieg.