British Hanger like a model 1751

[Kmaddock]

Hi All
I would appreciate some information on the attached sword.
I am new to this forum but have done as much research as i could to identify the attached item.
I got the item blind at a local auction , it was v v rusty and i have cleaned as much of the active rust as i can without getting down to the nice black platina
Very cautious bronze wool cleaning was all i have used and there is no sctatching on the metal work just deep inactive oxidation
I was delighted to find the running fox of Samuel Harvey of Birmingham on the blade, I have included close ups of the marking and i am confident enough of the identification
it looks v similar to a M1751 hanger but the guard is all steel and not brass and the brass handle is of rope work pattern and a bit different
The protective bars are a lot different as well
So it is not a M1751 but would anyone be able to give me any further information on this sword.
If no further identification can be made would anyone hazard a guess on the age of the sword?
blade length is 24.5 inches
any corrections to my above assumptions gratefully accepted

Thanks in advance
Ken