This might seem a bit crazy,considering your truck has low miles,and is practically new.But, for about $3100(free shipping in lower 48,a bit more for you folks,I guess) you can buy a NEW-FULL WARRANTY-GM performance 5.3.It has a different cam,and graphite coated pistons.GM claims 330 HP vs 295 stock.
Now a full performance exhaust will be maybe $800-good headers maybe $400-CAI maybe $200-figure close to $1500.Granted it is just 1/2 of the hot rod motor, but usually-usually-performance exhaust,CAI and Headers make a vehicle a lot louder, but just a tiny bit quicker. 35 hp will make you quicker.The "chip" can add performance without noise,so different story.
I'm old-56-and have done the headers/exhaust stuff,and I always got more noise than HP.Aftermarket systems frequently leave holes in the torque curve-they rarely work as smoothly as OEM stuff,and usually give up some torque down low for a tiny gain up top.The aftermarket guys usually lie/exaggerate about the real hp gains.
It is hard to beat the factory engineers now.The cam will trade some down low,for some up high.The graphite pistons will decrease the hp lost to friction.
Others no doubt, have had better luck with CAI,headers/performance exhausts behind the headers.
Of course,you can always add that stuff to a new GM performance motor.The rechipping might be a pretty good bet with the hotter cam-maybe rev higher,and get more hp up top.
Luck,
Charlie
PS I wonder if you can drop a 6.0 in there??