Demo model my ass, that is where my slide finish is worn from holster wear too and I have been carrying it for 6 years.
If this is a new gun I have a bridge in brooklyn to sell you.
If this is wear from test firing the gun will gall itself to death in a box of ammo or so.
Easy way to check is to take out the extractor and see how much carbon is built up in there.
Edit, just looked at your extractor retaining pin, the hole is buggered, looks like some one already went to town on it with the wrong punch or something.
I hope the seller took you out for a dinner and bought you flowers before ----- you.