If we (only) directed our steps to the possibilities of this hilt being the bust of an actual bird, what i find so far to have a similar figure are Calaus (Hornbills), namely the grey hornbill from Malabar and the Sub-Saarian hornbill.
Obviously this would be a 360º turn in all that has been discussed so far. But having no undeniable evidence, i am only taking care of not excluding other possibilities.
I once had a rustic sword made in (Ex-French Colonial) Africa, with a brass hilt undoubtedly imitating an European sabre, but with its pommel depicting a zoomorphic figure, apparently some species of hornbill.
In any case, this is an opportunity to share pictures of these splendid birds
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