Automotive Customizers(AC) are the only folks I know of who have them for the 2000-2004 Frontier/Xterra with the VG33. AC's Header Announcement 
You will also need AC's Check Engine Light-'eliminator kit'
Ask questions about the headers as they are a fairly new offering on the Nissan aftermarket.
BIG QUESTION TO ASK:
1) Are the gaskets included?
I wanna be like my 'older' brother when I grow up.... 
