Bought my AFX FX-16 from www.motorhelmets.com for less than $90.
Edit: And re: size. I went into a motorcycle shop and tried on ones until I found the size that fit. And FYI, if you are ordering an XS (like I did) you might have to wait a little bit. I was told by the rep that they don’t stock very many in that size. I had to wait about a month for mine to come in.