MADRID, Oct 5 (Reuters) - Spain’s Unicaja plans to cut 1,513 jobs as part of a cost-savings plan following the acquisition of rival Liberbank, a source with knowledge of the negotiations said on Tuesday. Unicaja, which at the end of July closed the 763 million euro ($885.69 million) deal with Liberbank to create Spain’s fifth-largest lender in terms of assets, was not immediately available to comment.