It is original, grip plate screws look messed with, this could be for two reasons, either someone removed them to look for maker marks or more likely they were damaged and replaced at some point, alot of these have chipped and cracked grips. The minor surface rust around the crossguard area would bring down the value.
Yes, it's an original.
"Much that once was, is lost. For none now live who remember it."
thank you guys !