I am unable to see yours at the moment but here are some of mine...
I tend to go for new versions of existing guns.
MP-5 XL- Long barreled MP-5:
UMP XL-
M-4 LMG- Kind of like how an RPD is like a long AK-47-
G-36S Sniper- There is a G-36 similar to a BR out there but this one is more like a true sniper-
Of course..... the Tactical Tommy-