No one makes a true cat back system for our cars sorry.
If its a stronger note you want you might try removing the resonator. That would leave you the stock cat and mufflers, and would cost less than upgraded components?
I agree, I had mine replaced Monday. Flowmasters, no resonator.
I do detect a 2000 rpm "edginess/slight rasp" when in first gear.
It bothered me at first. But now, EVERYTHING is better so , I can live wi' dat!