Jack the Dog has a nice one....

[SIGP2101]

Missing typical dimple in the center of the Swiss cross. Or is that because it was German manufacture but finished & barreled by Hammerli in Switzerland?

There is something about that trigger plate that it is ify, still not sure what exactly but it will come to me.

[Ron Wood]

Originally Posted by SIGP2101

Missing typical dimple in the center of the Swiss cross.

The dimple in the center of the Swiss cross is found only on the very early 1899 preproduction models. The dot was a registration point for hand stamping, as opposed to roll engraving, of the rays on the crest.

Originally Posted by TheRomanhistorian

Is it particularly typical for there to be that that outline in the safety area?

Yes,
That is how the safe position is marked on Model 1900 and 1906 Lugers

I do not necessarily agree that this gun has been refurbished. It may have been, but to my eye there are no obvious signs.