I know this isn't the latest and greatest and it's an older PCI-E 2.0 card, but it's a decent choice and the price can't be beat.
HP QLE3242-HP NC523SFP Dual Port PCIe 2.0 10Gb Network Server Adapter | eBay
HP QLE3242-HP NC523SFP Dual Port PCIe 2.0 10Gb Network Server Adapter | eBay