^^all very good points. Also most of this stuff you can buy from member on mr2oc. there are always people parting out their cars or selling these parts because they upgraded. But knowing that is what is removed i would probably just replace them with a CT26 and a Greddy type sidemount.
The only thing i dont understand is he says an OBX header was installed. That is for non turbo cars. So i would be leary that its even a 3sgte. So if you could give us a pic of the engine bay, that would help. But there is a big difference in the engine bays
3SGTE
5SFE
And of course the first tell tail sign is the engine lid. If the vents are totally flush with the lid then its a 5sfe