This is a so-called "short magnum" receiver from a 1960 rifle. The "short magnum" receiver was used for the .264 win mag, .300 win mag, .338 win mag, 458 mag, etc. (very different from the current definition of "short magnum"). This will work for all magnum cartridges, except the longer H&H magnum rounds. The recoil lug of this receiver is factory stamped "458", indicating an original "short magnum" receiver.
The condition of the receiver rates very good. There is some honest finish wear and a few very light blemishes, but no metal damage, pits, added holes, etc.
We use the NRA Modern Gun Condition Standards Grading System for grading part conditions. You can read about it HERE
NOTE: Laws governing transfer of firearms require that receivers be shipped to an FFL holder. If you do not hold an FFL or C&R license, you will need to enlist the services of an FFL to complete the transfer. If needed, we are happy to assist you in locating an FFL holder near you who can complete the transfer on your end.