Explorer,
I've found the Eley headstamps before and find there were most likely produced somewhere around the 1890's to 1920's.
Great headstamp and hard one to find.
Also your 38-56 is also a scarce one.
I have a 1886 Winchester in that caliber. It's one heavy gun.
Info straight out of Wikipedis...
The .38-56 Winchester Center Fire cartridge was introduced in 1887 by Winchester for the Winchester Model 1886,[3] and was also used in the Marlin Model of 1895. Production of Winchester Model 1886s chambered in this cartridge ceased in 1910 due to lack of demand,[3] while most commercial production of the cartridge itself ceased in the 1930s. New production loaded cartridges and unloaded brass cases are rare, and are often created using reformed .45-70 brass. The cartridge was originally intended to outperform the similar .38-55 Winchester, but in reality had very similar ballistics despite using more gunpowder.[4]
Great finds