Trying to get new muffler for '07 C15

I have an '07(pre DPF)9900ix with a C15 ACERT. I want to replace the stock catalytic converter type muffler with a free flowing type. Does anyone know if Donaldson or another company makes a direct replacement for the factory muffler or am I going to have to piece together a bunch of parts to make something else work. The truck has dual stacks and has a muffler like this one. This is a picture of a KW unit. Mine is similar but with slightly different dimensions.


I might be open to going with a muffler delete and running straights, but I'd have to have a resonator of some type to keep the sound down. I don't want to listen to the loud drone all day long or wake my neighbors up when I drive through town to my house.