I'd draw it by hand because its quicker than going to construct, spawning it, opening it in photoshop(which alone takes a minute to open), magic erasering the white out, changing the hue to red, resizing it, and adding a 1-2 pixel black stroke.
Also that just gives you a view of the weapon, not the effect it has(when you get shot by a rocket launcher, does it show a rocket or a rocket launcher?)