Idk about just the vent, but you can get the whole panel for $22.
https://www.subarupartwholesale.com/...waAoW-EALw_wcB
Also I think those two bolts are the same as the ones that hold the seal on top of the bumper for the hood. Confirm one fits and take it to the hardware store. It's likely an 8x1. 25