Quoted:


The butt-stock mag pouch, by virtue of its having internal snaps, will scar the stock of your Carbine.  Not a concern of most GIs, but maybe of concern to you.

Oiler is necessary to mounting the sling, of course.

One accessory that you didn't mention, but which will save you untold hassle is a bolt dis-assembly/assembly tool.  Trust me on this.  A reasonable supply of USGI spare parts, such as extractor, ejector, their springs, and firing pin is always a good idea, and will retain value always.  Unless the mags are brand-new, always consider their 70-year old springs suspect.  15-rd mags are usually trouble-free, but 30-rd mags are very troublesome for two reasons.  First is inferior OEM springs, and second is that lots of carbines do not have the 30-rd mag mag latch.  Lacking either will be very troublesome.  
Both problems are easily and inexpensively fixed

You left off a bayonet and scabbard, although some carbines were not originally equipped for them.  If yours was not, the original field knife issued with the early carbines in now quite expensive, and the later bayonets becoming so.

There are plenty of books on Carbines and their accessories.  some of them very detailed, and expensive, but the ones by North Cape  are fine for the owner seeking info but not yet obsessed.

FWIW, GI ball is much inferior to the round-nosed, exposed lead tip reloadable bullets for most intense social purposes.

Good little carbines, and well-suited to their original opurpose, which was to replace the hard-to-shoot-accurately pistol amongst second-line troops.  Jungle and very CQB environments, worked pretty well, except in intense, Korean cold––but perhaps that issue was user-induced.