The offset is dependant up the rim width, which you didn't mention....so the correct offset is not answerable yet.
The Stock offset is +40 mm on a 7" rim.
Its 25.4 mm per inch, so, for every extra inch of rim width (Over 7"), subtract 25.4 mm of offset, to get the correct offset for the new rims...that will give you a ballpark #, you can be off of that a few mm either way.
If you get rims with 5.5" of Backspacing, you should be OK as far as rub and clearance go...that IS hard to find in an aftermarket rim though....you might have to order it custom.
Personally, I'd rather set it up for function, rather than bling...but, the above should help you in your quest to pimp your ride.
_________________________
- TJ
2001 Xterra '03 VG33, SE 5 spd, 305/70/16's, Revolvers, UBSkidderz, Doubled AAL's, 3"SL/2"BL, winch/bumpers, skids, sliders, OBA, Snorkel, pine stripes....
Friends don't let friends drive stock.
http://www.gifsoup.com/view/501230/tj-tackling-crawlers-ridge-o.gif