There are two parts to this answer. If you could find a key (maybe eBay) it needs to be the correct type (shape and buttons) cut to match your key and then programmed to work for you. I don't know why you would look for source other than the dealer because there were ten keys made for your Z just waiting there to be ordered. If cost is whats sending you down this other path you might be better off just bitting the $ bullet instead of trying to find the right key on the outside market. I ordered a spare remote key just to give me piece of mind. I have not used it yet in three years, so maybe there's another option, to just live w/o it.
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