errr... those links are to 727 perf, not 737. Even if you look up the 737 charts, it all depends on whether you use FAR or JAR figures, what empty weight you use, etc.
The NZCAA may use the US type certification as a basis for approval, but that is because they have no choice! As you may have noticed from the 737 perf charts, the type certification is not approved in the same way as performance data is - hence the FAR and JAR figures. For a start, you would never use only a balanced field length when assessing runway performance.
It's all academic anyway, no chance of a -200 series 737 ever being used at PP.
It is true that smaller airports are popular with LCCs in Europe, but "smaller airport" normally means a runway of at least 1800m.