[Jim McDougall]

Keith this seems like a book illustration, you note other side hilt is same. What is the reference? context?

From the illustration, the example you have found is indeed close most notably for the tall urn type pommel, which as in your illustration is faceted.
These type of urn type pommels were from the neoclassic fashions and styling of Robert (1718-1792) and James Adam (1732-1794) whose mostly architectural designs (known as Adamesque) became in vogue with popular cut steel small sword hilts of Boulton 1780-90s.

These hilts as in the example you show were spadroons, sort of between the small sword (thrust) and heavy broadsword. They were straight blade backswords (single edge) and became regulation infantry officers swords in 1786. ...as noted by werecow previous post (this with brass and 'montmorency' style blade usually used by James Wooley of Birmingham....these I think were naval).

I am attaching from "Swords and Blades of the American Revolution" George Neumann, 1973...one of these 'spadroon' typw swords. While of iron, and of course the vestigial langet not congruent, it basically recalls the guard configuration.

So the anomaly you have illustrated is a conundrum, as it basically recalls the cast brass hangers of 1742-51 for infantry which were typically made in Germany after their patterns. What is confusing is you note the grip wrap is gone and replaced with copper wire....these hangers were solid cast.
Also the pommels were globular, not of this later 'Adam' form which came about in 1780s.

We can only surmise this saber is pieced together perhaps with similar type hilt, the 'type' faceted Adamesque pommel, and of course the 'Shotley' blade. Could this be the BTF used by Harvey mid 18th? many of which did not bear his initials.
In Neumann (1973) p.67 (18.S), an English hanger with same type blade has the running fox with H in center, shown period 1740-55
p.70, op.cit. (26.S) another hanger 1740-60 with BTF no initial.

These hilts are irrelevent as blades are same basically as your illustration.

It seems we have agreed that Shotley blades were filtering into Birmingham where many munitions grade arms were being assembled. While the 'fox' seems to have been notably present on many, Samuel Harvey applied his SH initials to many, less with H only and numbers left blank. Oley was the 'ghost' supplier of blades into Birmingham it would seem, and had been for some time as he is not mentioned or noted among recognized English blade makers.That is, until the blade trials of Thomas Gill in 1790s where among blades submitted for tests was Mr. Oley of Newcastle.,
It seems odd to have such an unusual hilt style, cast and with wrapped grip and later pommel form......though the presence of one of the apparently not uncommon BTF blades which had been coming into Birmingham for some time being used for assembly of an order of such swords. Perhaps surplus blades were used by an unknown cutler who cast hilts for the order ? Colonels of regiments supplied their troops and arms orders were at their whim or design.....even more so with militia units.