Perhaps this post will shed some light on your situation.
Perhaps this post will shed some light on your situation.

SFP TO RJ45 TRANSCEIVER SFP MODULE COPPER SFP OPTICAL PORT TO RJ45 ETHERNET PORT
$7.99
Cisco Meraki MA-SFP-1GB-SX Network Tranceiver Module
$89.00
NEW Sealed Cisco SFP-10G-LR 10GBASE-LR SFP+ 1310nm 10km *US Shipping*
$24.00
HP 557SFP+ ETHERNET 10GB 2 PORT 792834-001 788991-001 HIGH LOT OF 10
$70.00
Genuine Cisco SFP-10G-SR 0-2415-03 10 Gigabit Transceiver
$5.40
Dell Mellanox ConnectX-4 Lx CX4121C Dual 25GbE SFP28 LP | 20NJD
$25.00
HP 560SFP+ 10GB 2-port PCIe NIC Ethernet ADAPTER 669279-001 w/ (2) 10GB SFP+
$16.99
Dell Intel X710-DA2 5N7Y5 Dual-Port 10GbE SFP+ PCIe 3.0 x8 Network Adapter
$27.50
HPE 560SFP 2x 10Gb SFP+ PCIe Both Profile Network Card 669279-001 665247-001
$14.90
Extreme Networks 10GE X440-G2-24P-10GE4 16533 24Plus-Ports POE+ Switch UP
$127.00