hey, if you are still looking for wheels (no tires) , i have a set that will fit if you don't have the sports package. i did'nt bother putting them up for sale here since i didnt think anyone would want them, but they'd be fine for a cheap wheel just to throw on for winter. if thats all you are looking for.
18" Chrome Wheels
they are a +38 offset 18x7.5". they weight 23lbs. not gonna lie, they will be pretty sunk in, but just throwing it out there. I had to put them on my Z for a day or 2 when my rear wheels were stolen, here is a pic of how sunk they are.
let me know if you're interested, i'll sell them to you for less then my Craigslist ad since you're a Z forum person and i'd like to help out if i can, plus i have literally no use for them anymore.