HE-500 at Audio Advisor for $599:
http://www.audioadvisor.com/HiFiMan-HE-500-Headphones/productinfo/HMHE500/#.UvqAEbTJH-4
HE-400 for $299:
http://www.audioadvisor.com/HiFiMan-HE-400-Headphones/productinfo/HMHE400/#.UvqAnbTJH-4
http://www.audioadvisor.com/HiFiMan-HE-500-Headphones/productinfo/HMHE500/#.UvqAEbTJH-4
HE-400 for $299:
http://www.audioadvisor.com/HiFiMan-HE-400-Headphones/productinfo/HMHE400/#.UvqAnbTJH-4