The Troopers and Vipers are tops. Also Stalker, Sci-Fi, Airtight, Renegades Law & Order, and Renegades Storm Shadow(if you can find him). The Stalker makes for great headswap LBCs, so buy two and put Flint's head on it. As for where to find them I can only say good luck. It's been pretty hit and miss for awhile.
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