Lonnie, welcome to the forum.
I think we'd need to see pictures. I have seen new barrels with a serial number, but have not seen a renumbered, as they would just put it on. If it was under, i.e. towards the frame and 3 digits, i.e. 8,82 then it would be correct, above it, hmmm
That is the normal eagle proof, so it is just fine. The crown over a letter is what the others are.
Also, it is unusual to find matched magazines with a gun, so that might not be the criteria you should judge for a "matched" gun,
How much are they asking? I ask because buying books is more important than just buying a gun. In lugers it is easy to get taken by lack of knowledge
Ed