I can't say if those would work, but I have built a similar unit to this using these bulbs. It was very easy and works very well. I realize shipping will be an issue for you, but perhaps there is somewhere in NZ that will handle the F20T12-BL bulbs. I was able to find them locally at a lighting shop fo 9.50US each.
Originally Posted by Sean
Previously to building the box, I simply used 4 of these bulbs side by side in 2 separate fluorescent fixtures. I hung them so they were about 8 inches from the table surface with both plugged into a graylab timer. It worked great and only cost about 60 dollars.
Good luck Sean!