If your talking about the ones in this link, i've got the front one. New never used, i'd sell for $50 plus shipping. I sold the rear one about a month ago.
This is where i got both of mine front/rear.
The Z Store! Nissan-Datsun 240Z-260Z-280Z-280ZX-300ZX(Z31/Z32)-350Z-370Z Parts: Front "Z" Emblem, Carbon Fiber Base, 09-11 370Z