$129 is a steal for that saber, regardless of condition.
Other than cleaning off any active rust, don't sharpen or polish it!
Your quest now should be to find the proper scabbard. I've seen a few on the loose.
These sabers sell at gun shows for $600 to $800, depending on condition.
BTW, this saber was designed to be attached to the horse's saddle. It was not carried by the trooper. In use, it was purely a thrusting weapon. Therefore, the edges were not sharpened. Only the point mattered.
Some of the scabbards had little projections on the end, so they could used as poles for pup tents. Others did not have the projections.