Hi Dave

I'm pretty sure the NX5 went from 1993-2000, from 2001 on it was the NXA. So your 2003 would be NXa.

If you visit:

http://www.tsrworldwide.com/

and use the parts books on there, you can work out which model bike the forks you have come from.

If you have an NX5 let me know, I have a manual so I can look it up for you. If it's NXA, best bet is to try calling a race bike dealer.

Cheers

Dan