Mk2 2.0 16v/ Mk3 1.8T / Corrado G60 all run 280mm brakes - which are what you want.
you will need new hubs/bearings/carriers/callipers/discs/pads - I picked up a set for £80, but I imagine you will likely need >£150 for that. fitting isn't hard (but it's not a 5 min job)