I am not certain on whether you are buying aftermarket wheels or brand new from a dealership; but it seems you want less-beaten-up versions of what you have (assuming they're the 18" wheels).
If you're buying from a dealership, all you need to do is order by VIN number and they will get you whatever came with the car originally.
Nevertheless, there is a section of the owner's manual that lists the specs. The back side of the wheel also has that info.
Bolt pattern 5x114.3
Hub bore 66.1
Other info. some-oem-infiniti-wheel-specs-including ... 20199.html