You can give these guys a shot they also sell on ebay i have seen there robo cop props on there every now and then Looks spot on, http://www.timelessmovieprop.com/
you may have to contact them for pictures i don't know if they have any up on there site yet, i think there Ebay id is x_t_r_m if you want to check feedback.
hope that helps
Thanks for the info guys. I think timelessmovieprops is bruces partner in the robocop thing, I have some emails from them from a while back. I just sent a new email anyway. I would love an accurate robocop helmet