Your search for "c3kx-sm-10g" revealed the following:
Cisco C3KX-SM-10G Catalyst 3750X 2x 10GB SFP+ Switch Module
SKU: NSH-1224
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
$ 28.99
• Only 2 remaining
Call if you need more
NEW Cisco C3KX-SM-10G Catalyst 3750X 2x 10GB SFP+ Switch Module
SKU: NSN-7719
Condition: New
Shipping: Overnight Options
Warranty: 365 days
$ 142.99
• Only 2 remaining
Call if you need more