If it's just to strengthen then maybe:
Wingers - Bacuna (Groningen) , Sinclair (Swansea) , Nolito (Benfica)
Striker - Everton (Heracles) , Janssen (somewhere in Denmark) , Gignac (OM)
CB - Indi (Feyenoord) , Prestia can get good , Kruiswijk (Heerenveen) , Rolando (Porto)
I hope you can do something with this, I think they can all fit in the team some better than others