Engine £400-450
Gearbox (if you use it) - £175
Engine managment - £280 (self build and mapped) -> £thousands
Exhaust Manifold - £260 min (new)
Custom exhaust (you can't fit an off the shelf on) - £300 min
Suspension - £60 (springs only), £200-300 for a full kit
Brakes - £90 minimum for the full front setup
Plus there are LOADS of other bits needed, like fluid, adapters, etc. These all add up to a fair old chunk. £100-200 probably.
MIMIMUM total of that is £1665, and that doesn't inculde wheels, and stuff to fit the wheels etc. The more realistic figure is well over 2K.
You may get a few bargains etc, but thats a rough ball park figure. You will pay a fair bit for all that work to be carried out as well.
@fingers regarding stock ECU - You COULD do it, but you have to think about the ABS sensors, airbag sensors, converting the pedal int the car to fly by wire, a VERY different wiring scheme, code issues, and then the fact you end up with an ecu you can't tune easily.
I ran the 1.2 16v on the sei mpi ecu for a while, and it went ok, could probably run the 1.4 as well lol.
No offence, but this seems like another dreamers thread, you need to do a lot more reading about everything needed and involved
Kristian