I rooted around and found the oakley M strike frame kit that has a clear and shades lenses for around 80 bucks.
there's one on sale right now on ebay, but i say you test it out first. It fits me and most of my friends well, but theres a few that just didn't look right with it on =P
http://cgi.ebay.com/Oakley-Ballistic...d=p3286.c0.m14