Honestly the cheapest way to do it would be to grab a RB25DET front cut... can get them for around 2k and has the ecu, wiring, injection manifold, turbo manifold, turbo, turbo oil lines, turbo water lines and the motor is built for the turbo... I recently fitted one to a E36 BMW and made 340rwhp without touching the motor (just larger turbo) And you say you have the spare time so that can go into making the engine mounts, g/box mount and sump mods if your half decent with a welder and grinder
But if you prefer to keep things all holden and would like to go injection you will need:
Injection manifold (can use a VK one)
Possibly larger injectors? If you can find out what cc stock VK injectors are I can tell you how much power they will support
Second hand turbo's can be had for $200 or so... just abit of a gamble.... A GT28 would be a decent choice since it will be a pretty stock motor
Exhaust manifold will have to be custom made unless you can find a old strata kit to modify
EFI fuel pump $150
A return fuel line to the tank
ebay intercooler will do $150
Intercooler piping will need to be made
ECU, Haltech Sprint 500 is just over $1000 or a Megasquirt is $600
Will need to either lock the dizzy and use it as a trigger or its sometimes easier and always better to just set up a crank trigger, can get the parts for $150 then just need to work out how to attach it. Then could use coil packs in wasted spark
Weld a oil return line onto the sump
turbo oil and water lines $200-300
Custom dump pipe and exhaust
Not sure what stock 202 compression is, but 8:1 would be a decent aim
Pump 15psi in and it Might hold together and you might just make 200-250rwhp