If it was a cigarette lighter that was shaped like a pistol, would you have to ship it through an FFL?
If it was a cap gun, would you have to ship it through an FFL? Even if it shot plastic toy bullets from a spring-loaded 'shell'?
No serial number. No firing pin. No extractor. Won't shoot. Sounds like a gun-shaped hunk of metal to me.
You'll shoot your eye out, kid!