How much do you want to spend/How much work are you willing to do. This is really the only limit. As far as I'm aware, no one makes an OEM-specific gauge yet (Damn shame). I hope Mountune/Ford Racing come out with a pack similiar to the Focus ST.
If you want a digital gauge with an analog readout, Defi are a great company, then there's your standard Prosports (Not a fan).
If you want a pure digital gauge, Scan gauge makes an LCD unit, Autometer and a few others make LED "digital" gauges. There are some other options such as those that plug into diagnostic ports (OBDII) and bluetooth into you phone to display what the ECU is logging.
Realistically you're doing nothing but translating a digital signal (pressure transducer) so your options are pretty large. It really just comes down to what you want/how to do it.
P3 Cars Digital Vent Gauge (Boost +More!) for Fiesta ST now available!
