Hello Zac,
The only kit available afaik is a 1:144 Revell. I've heard that there has been a 1:72 Revell NH90, but it is out of production.
Since several European countries are about to receive their first NH90's I wouldn't be too surprised if Revell came up with a rebox of their 1:72 kit with new decals...
Good Luck!
Gertjan