XM-8 w/ 40mm M203 SUSAT 4X telescope sight
M249 SAW SUSAT 4X telescope sight
HK MP-5SD3 BSA Red Dot System
I Don't Think This Sniper Rifle Will Be In SOCOM III But I Would Like It As My Long Range Rifle System
CheyTac Intervention .408 Caliber M200 Sniper Rifle Nightforce NXS Scope 5.5-22X Zoom
At the ranges beyond 700 meters the .408 bullet has more energy than the standard .50 ball bullet, pretty sweet round.

CheyTac LRRS, including Intervention M200 rifle with scope, .408 CheyTac ammunition, and tactical ballistic computer
If you would like to know a bit more about this weapon check out this site
http://world.guns.ru/sniper/sn63-e.htm