A Supercharger will physically bolt on, though you will need the correct lower manifold.

You don't HAVE TO change internals, if you don't want to. If you don't change internals (done to lower the static compression ratio) you will end up with more power than a stock S/C setup.

Computer changes...Cyclemut might know.
Injector changes...same
Camshaft changes...same
Thermostat...10 degrees cooler for S/C model (thanks for the info Mut).

Other than that have at it! Stock S/C only puts out ~7 PSI...it won't kill it too fast.

Will it ping??? Maybe.

Do the Toyota's have pinging problems with their TRD 'Chargers...absolutely.

Power isn't expensive...it will only cost however much ($$$) you've got