Portions are raw steel which will probably have pitting, which you will have a tough time eliminating; portions are aluminized, which you will have a tough time duplicating that finish. Chances are you will have dents and scrapes, also. It will require some work with different processes to obtain a finish worthy of the rest of the car.
There might be a survivor car owner out there that would like to have your takeoff exhaust?
A few NOS exhaust components are around, but they get expensive. Then, if you are going to drive your car, you are right back where you started. You do have a high quality, reproduction option with the Scott Fuller products which offer your choice of raw steel or aluminized.