I could be way off, but I suspect the front and back blocks are not native to this body. I'd bet the body is a one-off, or a small run body, and then the blocks were added to make a complete gun. Kit/build gun overall.
Proto mask, Halo b, 48/3000 crossfire, redz 3+3 pack, dye lock lids
XSV fan club member #666
custom built cocker
2004 AIM swift body (blue to silver fade), A+ Anno bolt and backblock, CP reg, tickler LPR,MPP ram with QEVs, E2, CP 9 piece barrel kit, MQ valved
hybrid rail,CP on/off
ISO a chrome Shockteck beaver tail/snatch grip, if you know where one is or have one for sell PM me