I think you will find most of those replacement parts at www.50resto.com
As for the catback, since the tips were welded on, they wont be straight unless you buy a brand new replacement, I recommend mac! Or Get them refixed with new hangers! It seems like a good project car. Keeping working on it.
i think its funny though that they stole worthless junk like your side markers and door speakers, but didnt touch the wheels, rotors, any of the engine, or anything else that had any significant value.