Gentlemen,
The 03A3 is not the same rifle as the 1903 Springfield. The 03A3 was a cheapened version of the Springfield, and all of them were made during WWII, as a wartime product to make them fast and cheap. They were issued to U.S. Marines to fight in the Pacific against the Japanese, before the M1 Garand was put into mass production.
The pre-800,000 serial number issue does not apply to the 03A3, only to the 1903 Springfields made prior to and during WWI, by substitute factory workers who didn't know how to property heat the steel without burning it and making it brittle.
The 03A3s are nice rifles, primarily because they have a great adjustable peep sight. But, the metal they used was so hard that the bolt never slicks-up with use. It always feels "sticky" when you cycle it.
In my experience, sporterized 03A3s, regardless of how nice, are only $250 to $350 rifle. These rifles in original excellent condition sold for about $25 to $50 in the early 1960s. Due this cheap price, thousands were bought up and sporterized, often by guys working in their garages.
In my opinion there is simply no reason to buy one of these sporterized rifles, when you can find high quality rifles (like used Remington ADL) in the same price range.
Hope this helps.
Mannyrock