Check out the parts fiche, to start:
http://colorado4wheel.com/manuals/Jeep/KJ/Looking at 05kj_PARTS_FICHE.pdf, page 214-ish of the PDF... You'll find pistons, rings, bearings, etc.
Beyond that...
Head Gasket (you'll want to get the code of the existing one - apparently, three thicknesses...)
Engine cover gasket
Injector o-rings (copper, 4X)
Injector o-rings (rubber, 4X)
Supplier-wise, it's hit and miss. Google search for the part number to start. Factory Chrysler Auto Parts (
www.factorychryslerparts.com) and MMA Auto Parts (mmaautoparts.com). If you have trouble sourcing a particular part, recent threads here have listed contacts at VM Motori America - and they might be helpful.
Mark