The primary advantage of the Winchester 70 is CRF. From 1964-1992 model 70's were not CRF and the pre-64's as they are known as were the only option for CRF Winchesters. During that time ANY pre-64 sold at a premium, not necessarily because the rifles were better, but because that was the only way to get CRF. Today there are other CRF options including Ruger and Kimber.
Winchester brought CRF back in 1992 with their "Classic" line of rifles. They were made until 2006 when the New Haven plant was closed. Those are IMO the best model 70's ever made. Much better than the pre-64's. They incorporate CRF and all the other features that are important with modern manufacturing methods which resulted in better quality, better accuracy and better finished rifles. Quality did start to slowly go down after about 2000. The early guns with 6 digit SN's are usually trouble free. Even most of the later 7 digit SN guns are fine, but the odds are better that you'll get one with problems the closer you get to a 2006 made rifle.
There were none made in 2007 and only a handful in 2008, full production in the South Carolina FN factory didn't get going until 2009 and 2010. They have since moved production to the FN factory in Portugal. If I wanted a Winchester 70 being made in Portugal wouldn't stop me, but I'd prefer one made here. Also, the 2008 and newer model 70's have a different trigger and I much prefer the older style trigger.
Most people have no clue what the advantages of CRF really are. They don't FEED any better than a Push Feed (PF) rifle. Their advantages are a much more reliable, robust EXTRACTION and EJECTION system. The old style trigger was as bulletproof, rugged and reliable as any trigger. Those rifles were made to function in dirty harsh conditions that would choke most other guns. The problem is that almost no one abuses a rifle enough to ever see the advantages pay off. Back when O'Connor was hunting month long trips on horseback into wilderness area in harsh cold, snow, ice, mud and wind were common. You were several days away from any gunsmith to repair a rifle and they had to work even if dropped in mud or snow.
That is the primary reason they are preferred by dangerous game hunters. People incorrectly assume it is because they feed more reliably. Not so. But they will extract and eject rounds even when the rifle is filthy from weeks of use in harsh conditions. The new trigger is more complex and the reason I really prefer the older 1992-2006 Classics.
If you want to duplicate what O'Connor used I'd be looking for a used Classic Featherweight. Of course O'Connor had his restocked and the Schnabel forend did not exist in OConnors day. The closest thing you'll get out of the box is a Kimber.
This stock style is very close to the one on O'Connor's rifle.
https://www.kimberamerica.com/rifles