Level of RB to get if trying to trade OBJ

Have Antonio and Keenen Allen in a full PPR with no TE needed for Line up, just 1 flex spot. Or should i just keep OBJ in flex for whole year. 13 man bench Have Royce Freeman and JAy Ajayi starting with Kerryon Johnson, Jamal Williams, Matt Brieda, Bilal Powell, Alfred Morris, and Carlos Hyde sitting on bench.