What if I can do the tuning myself?
Picadilly:
Average stuff that you need to get when turbo a car from NA:
1. exhuast manifold
2. Turbocharger
3. Intercooler (recommended but optional)
4. Blow Off Valve
5. External wastegate (if you don't have built-in internal, or doing really high boost)
6. Piggy back / chipped ECU(or DME) / Standalone
7. New set of injectors (depend on your duty cycle)
8. New "colder" sparks if you running high boost application.
And some of the misc. like downpipe, intake piping, oil return, coolant line,
Is quite "alot" for a 1.8 to produce 300hp. And again, make sure you drivetrain (gearbox, torque converter, drive shaft, rear differential, driveshaft) can handle the power you are getting.
Turbo route is always fun, need alot of TLC and understanding.
Cheers