Hi Bryan,
The single-port 10GbE Network Card, Intel® Ethernet Converged Network Adapter X540-T1, costs around US$ 341.00. While a dual port gigabit network card, Intel® Gigabit ET Dual Port Server Adapter, costs around US$ 145.00 - 160.00.
ARK | Compare Intel® Networking Products
You can find other network card models and recommended prices here - ARK | Intel® Networking Products
Please let us know if you need further assistance. Have a great day!
Sincerely,
Sandy