Thanks everybody,
This one came from an estate bought out by a LGS.
In 1945 Remington Rand was wrapping up its last few contract runs.
One of the unique aspects to this gun is that it's manufacturing date can be tracked to within a day or two, and its most likely that this gun was made on June 7th, 1945. It was part of a 10 day run of 1911A1's made by Remington Rand in which they made the last 61k pistols of their contract.
As the war was in its last stages, instead of being issued many of these new 1911A1's were put into government storage in their original Kraft box.
Over the years many were issued, but in 1962 the DCM, Director of Civilian Marksmanship, the precurser to the CMP, released a large amount of surplus 1911A1's to the public very much like what they are doing now. For the price of $17.00, mailed to the DCM, you would receive a surplus U.S. government pistol.
Most of these were as they are now, mixmasters refinished and rebuilt with many having seen multiple wars. However, a small number of the remaining unissued Remington Rand 1911A1's were sent out along with the rest.
This is one of the only documented instances of the Remington Rands coming up for sale on the civilian market in unissued, like new condition. There were estimated to be no more than 500 Remington Rands in this condition released at this time, and it is unknown how many have remained in the original box in like new condition.
This is one of those guns, one of the last few remaining Remington Rands that remains in like new condition in its original box as it would have appeared in WW2.
Here is another example that came up for auction a few years ago.
https://www.rockislandauction.com/detail/80/3428/outstanding-us-remingtonrand-1911a1-pistol