1990 exhaust replacement

Hello, I just bought a 1990 deluxe xtra cab 3.0l automatic 4x4. The exhaust is rotten out. What should I do to replace it? Factory exhaust system or aftermarket exhaust system (all I saw was pacesetter after quick search). I don't know what condition the headers are in. It's late so I just wanted to get a head start on fixing it up.

Does anyone know if the old cat is worth anything for it's platinum?