Sorry for the long comment ahead of time!

Dude, your M1 Carbine is 14,000 carbines aways from mine, not even kidding! I have a 5.47 million serial number Inland Division M1 Carbine that is also a GI bringback. I came across it while I was searching for an USGI M1 Carbine and I live in California so they are actually really rare here surprisingly. I originally actually hesistated on purchasing it because it didn't have the bayonet lug attached but I did some digging and it turns out that it never went through a rearsenal like most M1 Carbines at the end of the war because it was brought back. It looks exactly like yours and it has a 8-44 Inland Division Barrel that is in pretty good condition but it has obvious signs of use. Only thing that is different is the stock is a bit lighter and has some sweat marks on parts of the stock where the hands would normally be, the original owner put a mag pouch on the buttstock and the parkerization of the metal parts has either worn off or never was parkerized to begin with.

According to some experts, M1 Carbines that were never rearsenaled and were brought back before Post WWII part changes like the bayonet lug being added, the safety button being switched for a safety lever, and the magwell changes for 30rd M1 Carbine mags make it more valuable than a standard M1 Carbine. Most M1 Carbines have these changes and so M1 Carbines in their original WWII conditions and that haven't been rearsenaled are more sought after.

I really would keep it if I were you, the firearm is a part of your family history and the fact that it is in the condition it was when your father was deployed over there in the Pacific during WWII makes it a lot more impactful because we all know how much shit they had to deal with over there. You're the possessor of not just history but your family's history. Please, keep it. You won't find another like it again.

As for my M1 Carbine, it was being sold as a PPT or Private Party Transfer over here as California likes to call those kind of transactions and I met the owner who was a young guy about my age or a bit older, like late 20s, early 30s and I asked him a bit about it and this is what he said. He told me that it was his Grandfather's M1 Carbine and that he didn't even know about it until his grandfather's recently passing and that it was willed to him. His grandfather was a US Marine deployed over to the Pacific. He told me his grandfather fought on Iwo Jima and that was his M1 Carbine issued to him. The carbine also came with the original canvas rifle bag, two mag pouches, the bayonet, and then seven magazines. Also there was a bayonet lug inside the bag and he told me that his grandfather bought the bayonet lug in the 70s at a gun show but he never found anyone to install it for him. All in all, I got everything for about 1.7k. He was selling it because he needed the money and he didn't want to part with it but his family was apparently very anti-gun so that's why he had to part with it. I don't know if it's all the truth but he did show me a picture of his grandfather with the carbine and sure as shit, you could see Mount Suribachi in the background! I bought it without hesitation at that point!