Inland carbine...
Lencac--If the .30 M1 Carbine in question is one from the CMP, they are all "mixmasters" as they call them--they've been re-arsenalled at least once since being made. The last new one was made in 1945, IIRC. Since, the US military has been using them, in Korea and early on in Viet Nam, and since then many of them have been loaned to other countries. The batch of Inlands from which my CMP carbine came, was used by the Italian police. When the CMP got them back, they went over them and sorted out the good ones, and re-arsenalled--again--any that were defective. That is, they broke the worst ones down for parts, and fixed the not-so-bad ones with the parts.
And any carbines that have ever been re-arsenalled, also got the newer, better, rear sight, the improved rotary safety, and the wider front handguard band with the bayonet lug, which is sturdier and makes the carbine a better shooter.
IMHO, this re-arsenalling does nothing to detract from the having of a piece of gear that was made for The Big One, and probably used in it. All the fix-it-up parts come from other carbines of the same age. There have been no new MILITARY M1 carbines made since 1945. (There have been commercial ones, made up of bought-up surplus parts. These are not regarded as being as good as the original-and-genuine military items.)
If you got one with a like-new bbl, the bbl it came back to the US with was shot out, corroded, or damaged in some way. It would seem that you got a particularly nice one, with that like-new bbl.
Now, if what you wanted was a collectors' item, then you'll have to get it from another source than the CMP. There are "original" and un-re-arsenalled M1 Carbines around, with narrow handguard bands, flip-up rear sights, and pushbutton safeties. I saw one like that @ a gun show last weekend. But it was $1000 asking price, wheras the CMP wants half that for the improved, re-arsenalled, version.
Unless you're a serious collector, with a well-filled wallet to boot, I'd not complain were I you. Just get some .30 Carbine ammo and some of the original 15-round magazines, get ye to a range, and start enjoying it!