I have a brand new never open, still in sealed plastic - Perrin drop in filter for any WRX 02-03 and would probaly work on 04s too. I am asking $35 shipped to anywhere in the US. Its the flat yellow foam one, no need to install anything just replace the stock one with this one, should take less than 5 mins. For pics, just check vividracing.com or pm me and ill try to get one to you.

 

Oh, filter will fit all imprezas 93 and up also.