Price isn't super but they're taking order s and claim to have it in supply - $0.79 ea. (100rd bags).
http://www.slickguns.com/product/federal-lake-city-556-xm855-62gr-green-tip-100bag-7999
http://www.slickguns.com/product/federal-lake-city-556-xm855-62gr-green-tip-100bag-7999