Hey just a guess, but from the looks of the outline for the backplate I would say either MAG 58 or M240 (same gun really). I have seen Blackhawk and Chinook helicopters in Iraq with these spadegrips before. I never really got a close up look through. Sarco had some M240 helicopter spadegrips kits for about $900. Looks like you are missing the modifided trigger assy that goes with the spadgrip and attaches inplace of the ground trigger assy.
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