can I reanimate the Arms.uasset. If so where is the .fbx

I would like to use the first person hands and arms that come with the UE4 contents to create a new animation. I will be working in Maya.

I can find the SK_Mannequin_Arms.uasset, but I need access to a .obj and or a FBX file. so I can import it into Maya and start working with it. Can someone advise where I can find the source .fbx files so I can reanimate them?

Or maybe there is a library of fist person hand animations I can use? I am looking for a sorcerer kind of animation, conjuring up a fire ball then casting it.

Any help on this is much appreciated.

Thank you.