There are two metal pop up vents in the top of the dash (seen in the pic). Then there are two plastic vents under the dash. You can see the driver's side. The passenger side one isn't present in the pic. It matches the driver's side. I don't think there's supposed to be one in the middle, but I'm not 100% sure about that.
Post #6 shows all the vents. It is good that you don't need the driver's vent, because I bought that a couple of months ago. However, go to eBay and search for this seller "oem-parts-from-the-past". Go to his store and the passenger's side vent and the top two vents should still be available.