If you find one cheap, great, but if not just make your own. If you don't have the DE, a lower plenum from the bone yard or Z1 who has'em for $48 will do and then just make your own.
Here's my thread where you'll find what to do if you're interested. Not a bad idea to get the aramid iso-thermal spacer which I write about as well. https://www.infinitiscene.com/thread....230572/page-6

Here's a couple of the threads I used to figure it out.
PHOTOS - https://my350z.com/forum/engine-driv...orting-10.html
DYNO OF PORTED LOWER https://my350z.com/forum/engine-driv...orting-33.html

 

 

theres one for sale now here on the forrum, post was right above yours