Many of the government contract guns were blued. Some polished blue, some rough before parkerizing was standardized. I have a pre-victory Jan 42 that is blued. It wasn't until later 42 when the government got its standardization requirements together to request parkerized finish, plain wood grips and V stamping. I have one that was acquired by the government and issued to Oldsmobile car factory turned munitions plant. It looked like a standard 1905 late model but had a lanyard ring and I picked it up last year for $400. Some went to the military and some to military industry. but real deal WW2 revolvers can be had that are not marked as V.
The serial number is the best way to tell and of course a factory letter.
You can sometimes pick up a pre-victory (No V stamp ) that was actually used in WW2 by USA relatively cheap as often owners don't check SN and issue to when it was made and delivered to and it isn't outwardly resemble a victory revolver (doesn't have plain wood grips or parked finish)