EA3500 App-Enabled N750 Dual-Band Wireless-N Router with Gigabit and USB

Any that can run OpenWrt. Any Wi-Fi card capable of AP mode is also capable of station mode. Most modern Wi-Fi cards capable of AP mode are also capable of simultaneously working in AP and station modes in the same frequency band. But stock firmware may or may not have these configuration options available. So you find an OpenWrt-compatible router, install OpenWrt onto it, and configure it the way you need. I used to do this with a pre-historic Linksys EA3500. Ideally, you want a triple-radio device (say, Linksys LN1301); that way, one radio can be dedicated to the wireless WAN connection, and the other two can operate in AP mode, each in its own frequency band.