You dont need to buy anyone. Danny Wilson does an immense job at LB for Liverpool. As does Insua on his return from Loan. If you have to buy someone, go for Marcelo in a structured deal (add after league apps amd after int. apps incentives) but keep your main offer under 10 million. After Marcelo moves on, try Bonsignore from Milan, Sakho in a structured deal, or Srna can play right or left (also a structured deal, should be able to land from Shaktar for relatively cheap, under £20 Mil in structured deal)