Amazon.com: 6 Port 2.5G Umanaged Ethernet Switch, 4 x 2.5G Base-T Ports, 2 x 10G SFP, Compatible with 100/1000/2500Mbps, Metal Fanless, Desktop/Wall Mount YuanLey 2.5Gbe Network Switch for Wireless AP, NAS, PC :
3Com Superstack II (3C16980) 24-Ports External Switch Managed stackable for sale online | eBay