Which of these RBs should I be shopping for a top WR

Im looking to make a move for a Top WR… right now I have Julio, Kupp, Golladay & Callaway
Im really deep at RB so im looking to make a move and package a couple of them for a top WR…

Half Point PPR
Im thinking about targeting Keenan Allen or Hopkins as both those owners need RBs… Who can I afford to give up without hurting my team to much? Who else should I target?