[alanint]

It is more than just opinion.

Lugers within a certain date and serial range have known and proven features. If an example is presented with features that do not correspond to every other example that is known or has been documented, chances are that the pistol presented has been altered.

Maybe the vet did acquire it as is. That does not mean it left the factory that way. High end collectors look for factory original guns. Any alterations, regardless of how they occurred, lower market value.