Bite the bullet and just put up with it until you can save up to get a ridiculousy oversized front kit. :lol:
Seriously though, you're almost better off just saving and going into a panelbeaters to spray the whole bumper. Any touch-up will just be annoying to look at because YOU know where it is and you'll keep looking at it everytime you're in a position to see it (trust me I know this :-? ).
If you are still considering using a touch-up paint, there are a few paint shops around that will mix it for you. One I can think of is in East Tamaki, on Greenmount Drive. Needed a custom paint mixed up awhile back and they came through fairly cheap, and in an aerosol can too. Just mask the area off as best you can, wait for a non windy day, and make sure there are no bugs around (a mate found that last one out the hard way :lol: )