Ian,
A MET head dress is IDed as Janus and said is "Headdresses covered with leather are made by many different peoples living in villages along the Cross River and in Cameroon.
Another site says Ejagham/Ekoi people in lower Nigeria and western Cameroon,
Here's the link with pic:
https://www.metmuseum.org/art/collec...0in%20Cameroon.
Regards,
Ed