Your search for "10051h" revealed the following:
NEW Extreme 10051H 1GB BASE-SX 850nm MMF LC SFP Transceiver
SKU: NSN-7132
Condition: New
Shipping: Overnight Options
Warranty: 365 days
Extreme 10051H 1GB BASE-SX 850nm MMF LC SFP Transceiver
SKU: NSB-3558
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
NEW Extreme 10051 1GB BASE-SX 850nm MMF SFP Transceiver
SKU: NSN-0783
Condition: New
Shipping: Overnight Options
Warranty: 365 days