In 1808 the Federal Government switched from a flat-topped hussar type hilt to a bird's-head pommel type hilt. In 1801 the State of Virginia issued a contract to John Miles of Philadelphia, PA, for 1,000 cavalry swords. These swords had narrow fuller that ran along the spine of the blade on each side. In addition, it had a slight ricasso at the hilt.
View attachment 488615Miles Hilt
View attachment 488616View attachment 488617 The previous example has been way over-cleaned. On one side of the blade you can see where it was stamped with the uni it was assigned to.
In 1808 or 1810 the Federal Government contracted with Nathan Starr to furnish swords. This is because swords have been found with"US".
View attachment 488619View attachment 488620View attachment 488621The previous example shows a Starr sword that was stamped "N STARR" on one side in a small channel and "V" for "viewed" on the other. The next three images are from another Starr sword with the same "N Starr" stamp on one side and "US" over what appears to be a "V". The two grips are a little different as well as the two blades.
View attachment 488622View attachment 488624
View attachment 488623
So there are three examples of swords with similar fillers but only the Starr swords have a lower ferrule. While an old sword blade may not be the origin of your knife, it seems to have acquired traits similar to some Starr swords from around 1808 to 1810. There were a couple of sword makers, whose names escape me and one or both of whom worked for N. Starr in his sword making operation. One of my books has the picture of the only known example of a Confederate sword that they meade. Perhaps they spent more of their time on knives.