second goalkeeper:
Francisco Guillermo Ochoa (around 2.5m-5m)
defensive midfielder:
Lucas (liverpool) this kid is amazin and might cost a bit but should be able to get him with your budget as i got him for man utd for 14.5m but that was in second season when his price has gone up
Striker:
try Micheal Owen usualy they accept a bid round 9m which is a complete bargain if u ask me
or try martins which can be gotten for roughly 12.5m
if u can wait i would suggest once it gets to either december 31st or january 1st and go to player search then filter then contract status and expiring and u can get some class players for nuthin due to ya bein able to offer contracts to them and then they will just join ya club once their contract runs out which is usualy end of season | 
