You can fit 256mm brakes from a big block sport or GSi, or you can use 284mm turbo brakes or 288mm v6 brakes.
The 256mm ones are easiest to fit. The bigger ones need drilling from 5 stud to 4 stud.
I have the 288mm ones on my 1.6 and they're really good. The pedal travel is a bit larger but well worth it.