Very late Remington M1903A3s are often found in original condition because they received very little (if any) use before being put into storage. A two-groove barrel is correct and as a rule, show little or no accuracy difference from a four groove.

Until a relatively short time ago, inspection markings on a stock were seen as a "liability" and were often sanded off. A correct stock of a rifle of that "vintage" should have an FJA and an RA, as well as the "circled P" you mentioned.

Can I ask what you paid for it?