Trade could be key to season.... advice?

We are struggling to find a RB # 2 in our fantasy league ( McCoy is # 1) . We have very good WR so they offered some of these guys for runners . He sent a message back with the 2 I was interested in. MedlinePlus MedlinePlus We offer either: MedlinePlus Jordy Nelson , GB MedlinePlus Marques Colston , NO ( I'm leaning towards here ) MedlinePlus MedlinePlus What we have to offer : ( All options seem less decent ) MedlinePlus Rashard Mendenhall - PIT MedlinePlus Shonn Greene NYJ MedlinePlus Lynch -SEA Marshwan MedlinePlus Willis McGahee , DEN MedlinePlus MedlinePlus Our RBS : Delone Carter ( IND ) , Jonathan Stewart ( CAR ) , Daniel Thomas ( MIA ) MedlinePlus Their wide receivers Antonio Brown ( PIT ) , Hakeem Nicks ( NYG - Hammy battling injury ) , Santonio Holmes ( NYJ ) , Miles Austin ( DAL -out 2-4 weeks ) , Robert Meecham ( NO) , Nate Washington ( TEN -Hip Injury ) MedlinePlus MedlinePlus We started 2 offices and 3 wide receivers in league one touchdown . MedlinePlus MedlinePlus What is the best for me and why ?