Lock appears to be replaced, and not really a great match. But, this being said, it matters little, as the rest of the gun is cool. Now, I will go out on a limb and posit that of the lock, stock and barrel, it is the lock that is of least importance.
My rationale: as an engine is the "heart" of a car, the barrel is the "heart" of a rifle. All is built around it. If it isn't right, nothing good can come of it. As for the wood, that should be self-explanatory. It engenders the style and overall architecture, if nothing else. And it is that little patch of art, often found on the cheek side, occasionally raised, but more often incised, that makes some grown men go "ga-ga, goo-goo" and pay ridiculous sums of money just to say they own it.
That leaves the lock, often broken during service and replaced. More often than not, the one you see wasn't there when the gun was built. No matter, it's the rest that makes a gun. And, yes, there is synergy here, too; that is, the sum of three great components is far greater than the sum of the three parts assessed separately.
