Hi AMT.
I suggest you open your options up. You can't have the best of everything, i.e. older car, low mileage, exact wheels etc and not pay a premium. View a car based on condition, and history, then worry about the wheels later.
Rays are not that expensive to buy second hand, new tyres on the other hand can be.
Are you checking consumable items on the zed's you have viewed? pads, dics, tyres etc? Everything adds up. Find a car that is in great condition, and don't worry about the mileage and the wheels on it. There is LOADS of cars out there, and it is a buyers market.
Why don't you sell your Hyundai for cash, save hard and buy, cash? You can get an early UK zed for £6-7k now...
I wore an old jacket of mines a few weeks ago, and had a receipt for £91 of V-Power that I put in my zed a few years back... I couldn't believe I was putting that in every week just to commute to work.
The 350z is a great car, but I certainly don't think it is worth taking 3 year finance out on a car that is 7+ year old.
Best of luck in your hunt, if you need any help.. i'm local.
Stephen