the name brand cameras can be pretty expensive; to me, the minor additional features weren't worth the money. there was no way i wanted to drop over a hundred on a tiny rear camera.
some of us have gone with e-bay cameras that work perfectly fine and are built into an assembly that snaps into one of the rear license plate lights so that no bumper drilling is needed. your linked camera looks to be of that vintage, but i think you can probably find a cheaper one that's of similar quality. search e-bay for "livina rear camera" and you should find plenty of options. nissan livina rear cameras are compatible with our z's.
nissan livina rear camera | eBay
also search our forum for livina, and a few worthwhile threads will pop up. in my build thread, i've got a few pictures of this type of camera installed on my last z.
they are probably not as reliable as a name brand camera, but at $20 a pop, you could go through five of them and still be saving money. night vision is not great with these, but it does the job.