sagebel
Stock? Pfft!
Tymarperformance.com I think they go for about $175. The filter is a paper element that costs about $23 to replace. Or you can build your own with some cutting of the stock air box and some 4" exhaust tubing. I'm not sure what mods will void the warranty. I know that some dealers were looking at the back of the PCM to see if a chip was ever installed. I have also heard a rumor that they could tell if a programer was installed and then removed. I'm sure someone will come along and correct me if I am wrong.
Scott
Scott