Those items pop up on eBay, but they are usually from salvage dealers, overpriced, and pre-damaged. It is nearly impossible to find used ones that aren't damaged.
I scraped those up badly in a crash on the right side. After a lot of research I decided it just wasn't worth the money to fix it. I tried to repaint the silver fake "air duct" cover, but the results turned out pretty poor. Ended up slapping some reflective tape over the scrape instead.
I even called a few local body shops about repainting it, but they said motorcycle paint codes are "meaningless" to them.