Walker Quiet flow mufflers ?

Good luck on getting part numbers. I emailed Walker technical support for a list of Quiet Flow mufflers -oval, offset 2.5" inlet, centered 2.5" outlet, aluminized steel. Guy keeps telling me if I will give him the length, he will try to match a part number. WTH? - how many damned 2 1/2" oval mufflers can they make? Must be at least three, maybe four.

In the same vein, I emailed Summit asking who manufactures the mufflers on their 2 1/2" exhaust kit and the specifications. They email me and tell me that the manufacturer is not in the listing. Damn, I can read the listing, why did they think I asked? If they aren't proud enough to tell who manufactures their product, I'm not stupid enough to buy it!
Sorry for the rant. I guess I'm being too picky by wanting to know what the hell I'm buying.