Kurt, thank you for the response. Now that I have been able to 'hit the books' I can see in Elgood the illustration of the Omani sword which is typically associated with the interior regions, and the scabbard does have this interesting pattern motif embossed in the leather (p.17, 2.13).
These pronged pommel type hilts do seem widespread in use and from the 17th century (possibly earlier) and probably well through the 19th. In looking at various examples of these,one example ("Arts of the Muslim Knight", Furisiyya, Milan, 2008, p.77, #41) with the same type hilt, but single downturned quillons, is shown as having been captured at Battle of Oran (Algeria) in 1732). These are shown as 'cutlasses' and often found in naval context throughout the North African littoral. This same type hilt on a sword also pictured in Elgood ("Arms and Armour of Arabia" p.11, 2.2) is strikingly similar in profile, but subtle variations in decoration and blades. This may well be the one mentioned from Stone as well, as the 'tortoise shell' is mentioned in all representations.
It seems these were notably popular in Ottoman association (particularly in N.Africa) and examples of these in Ottoman context are known from as early as the 16th century. The influence of the hilt form seems to have diffused into the Deccan in India in the 17th century as hybrids of the peaked pommel or pronged, are seen with Ottoman type quillon terminals and Indian langet. The linear design of rosettes on the hilt faces similar to yours bring to mind that Hyderabad produced swords for export to Arabia, typically Hadhramaut in the 18th century. Many have these same type discs in motif.
Elgood notes these cutlass type swords with such pronged hilt profile are well known on Arab maritime routes. The coastal region in Oman, Muscat, is the trade power which also controlled areas beyond Zanzibar, which included parts of North Africa including Libya, Algeria and Tunisia in commerce. The Ottomans were driven out of Oman by Ahmed inb Said of Yemen in 1741.
All of this seems to show distinct links in Arab maritime provenance to this type of sword, and hilts of this form with profound traditional presence. The heritage of the style from North Africa, connections to Arabia through the Yemen, particularly Hadhramaut (and sword influences between Hyderabad and Deccan), and the Omani type leatherwork in scabbard with Arab type cord and fringed swag trappings present hybridization noted to be quite well known in these type swords.
As usual, just thinking out loud here, and that this cutlass may well be quite old and simply newer scabbard, and in ivory/gold for someone of importance in trade connected to Oman's networks. It seems the merchant class in Oman were quite status and fashion conscious, but they typically carried the cylindrical hilt kattara.
Obviously these ramblings dont present anything conclusive, but hopefully the elements noted will offer possibilities for consideration and maybe even some discussion
Extremely exciting piece there!
All best regards,