What about maybe just a k&n air filter?
I put a reusable K&N filter in mine. I can’t really tell any difference, but I also haven’t dyno’ed it. Mostly I did it because i’m at high altitude (10,000’) and wanted to get as much air as I could. That, and I’m lazy and like the idea of not ever having to buy another air filter. Just rinse, spray, and replace.