/give @p minecraft:player_head[
minecraft:profile={
properties: [{
name: "textures",
value: "eyJ0ZXh0dXJlcyI6eyJTS0lOIjp7InVybCI6Imh0dHBzOi8vdGV4dHVyZXMubWluZWNyYWZ0Lm5ldC90ZXh0dXJlL3VuZGVmaW5lZCJ9fX0="
}]
}
]
I noticed there weren't a whole lot of mechanical left arms, so I made an edit of an existing skin for myself and others.