if you're looking for headers and/or exhaust for the 1MZ-FE you could check out the following:
Greddy, A'pexi, XERD, JP Performance, JIC Magic
XERD, JP Performance
I would highly recommend some suspension mods in addition to your planned engine swap.
Whiteline (swaybars, get em at ctmotorsport.com)
Eibach springs (I think Tein too)
Toxico or Bilstein for struts
JIC Magic FLTA2 or FLTA1 (coilovers)
I don't know if these would work on your model year but it couldn't hurt to shoot them some mail.