[Jim McDougall]

Thanks guys!
These comparisons found in Dean (1928) offer some clues indeed, but as previously noted, these small sword hilts were artistic creations, often privately commissioned, so any sort of consistency or other like examples is most unlikely. What can be seen are general trends or favored styling in the motif.
The only small sword maker I am aware of having 'pattern books' would be the cut steel hilt patterns by Matthew Boulton in London latter 18th c.

What seems unique in the example in OP is the vertically gadrooned grip which seems almost 'feathered' as well of course as the most unusual double head eagle. While as noted earlier, these Byzantine style eagles were heraldic in the arms of Russia, Austria and several countries, but more specific use in individual heraldry seems elusive.
It does seem that Masonic heraldry does use these in variation for some of the degrees etc. but this version seems more stylized than copied.

Perhaps it might be a personal interpretation simply recalling one of these possibilities artistically, or possibly some fraternal group or order ?

The hexagonal blade, atypical for small swords as a rule, does seem more weapon like, recalling the 'dragoon' blades of 18th c.
The ellipses in that floral pattern are exactly the configuration I was thinking of.


Interestingly, the M1796 officers sword had pretty much this shape guard so it seems to have become popular 1770s-90s and been known across Europe. The small sword itself had become pretty much outdated in civilian terms and military officers dress swords followed a heavier version of the style in 1790s.