That's a nice hammer gun! I usually always prefer straight grips over pistol grips. Though I have more pistol grip guns. My only straight grip Top Action hammer gun is in 10 gauge.
As Dean mentioned the lever on yours has more engraving that a typical zero grade, but that wouldn't necessarily mean it is a replacement. And if it was at least it was an upgrade of sorts...
Anyway, nice gun and you have me wanting to look for one for my collection
