Internals? Why? You can get a complete ecotec for about $7.50 off the side of the road. Maybe valve springs but not much more internals wise.
Better still just grab a low km l67 bottom end throw an ecotec plenum on it - run 14psi all day. Find a good tuner and you shouldn't have any issues with the motor.
This guy does pretty decent ecotec/l67 turbo kits.
Cost wise though, depends. A new raptor kit costs what, 5k - with no intercooler setup. Looking at their website the base kit includes upgraded injectors but I can't see a fuel pump with the kit. Personally, I'd always run a rising rate fuel reg (more boost, more fuel) and a surge tank but that's just me. Nothing against raptor they're great kits and they stand by their products, but i'd be costing up some turbo setups before you make your choice. You'll make more power and the torque curve of a turbo car never gets old.
Food for thought.
Well yes, V6s are awful. V8 every time