It could be elephant, depending on which part they used, but my vote would be for walrus or maybe seal.
The elephant pieces I"ve had/handled had a slightly different grain (more very small, uneven circle grain patterns). Walrus, though, at least with the belly or back area, tended to have those big gnarly graining. As well, walrus (or seal) was often used in vintage cases.
Without seeing/handling it in person, I'm not sure so am just guessing.