M1 Garand Front Sight Screw.  Rob's pick of USGI, used.  For $5 Choose Left, beveled (correct for early guns with screw seal) Right, smooth head (later), or not pictured knurled edge for late and rebuilds.  If you request one marked the "A" on the inside of the hex keyway they are $25.  E-mail first for any special requests and I will make you a custom order.