Very nice pieces.
They look to be in good condition, this points to them having been removed from Africa when new. Only path to easy dating is tracing their history. Another pointer would be the fabric, is it hand or machine woven. Wood sculptures in tropical countries have a relatively short life typically <100 years. I would guess these to be relatively modern. Problem with books and stuff on the web is it mostly illustrates museum quality pieces that left Africa long ago. Popularity in Europe started with the artists of the 20s/30s.