Welcome to the forum, Paolo
You have a very nice little knife. It's definitively African (and without any doubt from Congo), but I'm not sure of its exact origin (tribe).
The iron binding on the handle is indeed similar.
Don't be worried about the size of your dagger. A lot of miniature knives and daggers were made in Congo.
Here are two other small daggers from my collection.
The one on the left is a miniature dagger from the Saka-, Mongo- or Kutu-tribes. Total length : 27,5 cm. Length of blade : 14 cm
The second one comes from the Tshokwe-tribe and measures 23 cm (blade : 13 cm)
