There are sporterized 1903 Springfields, many of which were made up by a owners or gunsmiths by simply replacing the wood with a Bishop or Fajen stock. There were others made by master gunsmiths, which I think is the rifle the OP started this thread about.
Then there are the 1903 NRA Sporters that came as new items from Springfield Armory with the 1922 stock (sometimes called the NRA stock) , a Lyman 48S rear sight, a slightly heavier barrel than the issue 1903 barrel and a beautiful rust blue finish. These were made from 1923 into the middle 1930's.
In my collection there is a custom 1903 Springfield made by Bruce Dawson of West Plains, MO. He used an original 1903 barrel which he slimmed down. In the rear end of the barrel there is the remnant of the slight groove that I mentioned in my previous post. The groove lines up with serial number on the receiver. The only thing that gives me pause in my speculation of the history of #1235002 is the star guage mark at 12 o'clock on the muzzle. All I have seen or read of were at the 6 o'clock position. FWIW
Additional comment
Thanks to Sunray for posting the link to the thread from 2009. I was surprised to see that I also participated in that thread as I didn't remember it. I am happy to see that what I said back then agrees with I said today.