Coach Steve Holland told BBC Radio Stoke: "We'll just have to keep trying. We could do with two new strikers, not just one."
He added: "We had a good go at signing McLeod (Charlton Athletic striker Izale), but he decided to go to Colchester instead because he wanted to stay in the Championship.
"There's no other answer - we'll just keep trying."
Former star Steve Jones of Burnley is another potential target.