Are you looking for a true dual or a single in dual out? I just got mine done at a custom exhaust shop. They did not even care if it was single cab, quad cab or mega cab. Total price was $420 for a single in dual out. All stainless steel mandrel bent pipes with tips.
Definitely depends on what you want. If you want true duals then it's not going to be extremely cheap, but I got mine done for $380 down here in Georgia. I bought two High Flow cats at an auto parts store down here for $150, then had the guys at the shop mandrel bend my pipes, got two Flowmaster 40's and chrome tips done for that price.
I DO NOT suggest you buy a pre fabbed bolt on kit online. The pipe is insanely expensive and sometimes doesn't fit right. Ask around to find out if anyone has gotten their exhaust done in your area, see how they liked the shop and worst comes to worst look online for reviews of shops in your area. I would suggest going to a mom and pop shop that has good reviews. Living pretty far away from a major city definitely helped me out on costs, so I am not sure how much it will run you. So instead of paying the nearly 700 bucks for a magnaflow cat back exhaust you can get true duals for less than that and save more on gas mileage. Hope that helped.