Your search for "c3850-nm-4-10g" revealed the following:
Cisco C3850-NM-4-10G Catalyst 3850 4x 10GB SFP+ Switch Module
SKU: NSH-2537
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
$ 194.99
• 8 in stock
Call if you need more
NEW Cisco C3850-NM-4-10G Catalyst 3850 4x 10GB SFP+ Switch Module
SKU: NSN-1790
Condition: New
Shipping: Overnight Options
Warranty: 365 days
$ 499.99
• Only 2 remaining
Call if you need more