Bumper in that pic is a Mk4 Golf Bumper, and can be had anywhere really (breaker/dealer). Now I am not clued up on how you would go about modding the Mk3 to take a Mk4 front end, but at the least you are looking at Mk4 Bumper, Lights, Modification to the front panel to take the lights, Modifications to the wings also. It's a lot of work, and then you would have to either smooth out the rear also or buy a Mk4 look bumper which can be had at AwesomeGTi to get the same look. And you should end up with something like this...

Entirely upto you mate which way you go, but me personally..
I would just smooth the front and rear bumpers of the Mk3 if you are after a cleaner look. Just don't think the Mk3 pulls off the Mk4 bumpers all to well to be honest, but that's just my opinion and and not gospel
