Toyosport manifold and exhaust rs200 too loud

Hi guys as above really, I just bought the car last night but cannot live with the drone and boom . What is the easiest ,cheapest, thing I can do to quieten it down? Could I fit a silencer in the original place one would be on the OEM exhaust? Thanks
 
Swapping the manifold for an OEM one would be my first step. Which exhaust system is fitted?
 
I was thinking something like this. I've been looking into it as im a newbie on these ,would a resonator do the same thing welded in ?