[Jim McDougall]

Beautiful sword!!!
I finally found pics of one of these sa'if I have had for many years. The hilt is of course more toward the 'karabela' style (often termed hawks head in some Arabian parlance) rather than this style which is known in same contexts.
According to what I recall from Lebedynsky these are of 18th c. but certainly would have been from later as well with traditions continuing.

Mine has a highly polished blade as well, which I always shuddered at the thought of it being chrome, but resolved as here that it was highly polished.
It has an inscription which I take to be commemorative as it reads"
"...the Islamic sword named after Muhammed al Hassan, the commander of all Faithful, the one who God choose victorious, was drawn in the year 1119H."

The year I believe is 1689, but I am uncertain how accurately I have relayed this or the inscription. However it does as noted seem commemorative.

The motif in the silver repousse does correspond with similar found in Hyderabad, and as has been noted, there was a long tradition of Yemeni (Hadhramaut) mercenary forces to Hyderabad and much of the mounting seems to have been made there.
The styling also includes very much Arabian character such as the 'aghrab' at scabbard throat mount.

The scabbard here is also of interest as it is with silver band wrap gadrooned over red velveteen, an affectation known well in Bukharen context. It seems discussions here some time back revealed strong ties between Bukhara and Yemen religiously and diplomatically. While this suggests a Yemeni production but could have of course been transmitted to Hyderabad and filtered into the making of mounts there.

I cannot see the curious mount above the baldric rings, but agree with Fernando, this is I believe to secure the sword in the scabbard. It seems I had read somewhere it was something like a 'safety' on a pistol, and indicator of peaceful contact despite a weapon being worn, where such was considered a threatening or disrespectful demeanor.