Id aim for a late DE 350z for this budget and that way you possibly dont need to spend the lot either (tax and insurance needed from the get go) IMO the extra paid in tax year in year out isnt worth it for the 06 model, i dont hit the rev limit every day nor do i feel the need to with the DE extra low down lb-ft I rarely have a drink in the car to which id use the facelift door cup holders either *early models have one on the dash anyways. Lamps on the 06 model are nicer than that of the early model, however interchangeable anyways. Also imo the DE from bumper is cleaner looking than the facelift ones.
Try and get one thats had recent tyres, brakes, clutch and exhaust as i did and thats £1000's worth that you then wont have to find anytime soon. When i bought mine in Sept 15 i had a budget of 9k and still went for a grey 05' model and its been bliss. Missed out on a black GT4, however with my ocd that was probably for the best