You can't find them, because they don't exist.
But I think I know how it works, even though I did not do first person hands and chose to use the third person model instead, because I was lazy.
So what you need to do is ignore the first person hands and gun for a while and finish your third person or regular player character, animate him and implement him.
What I did was put a gun into his hand and so I could give him animations for the gun, like reloading it. So I was left with a third person model and a gun, so I removed the gun and exported him. In-game I then would mount the gun onto the hand and everything lined up nicely.
If you finished those steps of implementing the player, then you can consider using first person hands, since they give you more control, look nicer and prevent clipping. I'm not a fan of those, since they mean extra work, which I will explain now.
To now make first person hands, you take your player character, you already have, that has it's origin meaning the position below the feet at coordinates 0 0 0 aka the objects origin and move the eye point of the player character to coordinates 0 0 0.
The reason for that is, that the gun gets mounted on the camera, aka you, aka coordinates 0 0 0. Now you should have a full model of the player character with its head at the origin point.
That's your first person hands now, of course you can delete the other parts of the model now except the hands and animate them more detailed or add more model details, though you should derive those extra detail from the first model you made, since the arms have to match up the player model, so you need new arms for every model.
Now you may wonder how you do different weapons, well I think that is done by adding the hands into the first person view of the weapon, so the weapon and hands are glued together, this has the benefit of the animations matching up perfectly. If you have similar guns, you can re-use the hands models and just switch the weapon.
Well those are the steps I think. It is a bit complex, that is why I dislike that system, so if you can get away without first person arms I would go that route, if you want high quality, make them. Later you also get more work, since the third person player model needs to roughly match the animations of the first person, so when you open the default Torque3D soldier you can see new sets of animations for each weapon, since the player walks, shoots etc differently holding each weapon.
This may sound complicated, but if you go through it step by step, you should get it done, if you have more questions just ask me.