You need
4900M 4 port 10GE half card with X2 interfaces (WS-X4904-10GE)
OR
4900M 8 port 10GE half card with X2 interfaces (WS-X4908-10GE)
WITH
Cisco OneX Converter Module Converts an X2 Interface into One SFP+ Interface (CVR-X2-SFP10G)
I would recommend you to use following DAC cables from Cisco.
• SFP-H10GB-CU1M: 10GBASE-CU SFP+ Cable 1 meter (Version -02)
• SFP-H10GB-CU3M: 10GBASE-CU SFP+ Cable 3 meter (Version -02)
• SFP-H10GB-CU5M: 10GBASE-CU SFP+ Cable 5 meter (Version -02)