Looking for an all-in-one outdoor networked GPS receiver for NTP purposes

I'm looking for a networked GPS receiver with the following features:

• Designed to be mounted outdoors on a pole/tower
• Serves as Stratum 1 time source
• Powered via PoE (I can give this one up, but it would be ideal)

Does such a device exist?

I know that Ubiquiti and MikroTik both make outdoor devices with GPS receivers, but it doesn't seem like you can use them as Stratum 1 time sources. (Ubiquiti just doesn't expose this functionality that I can find, and MikroTik says "maybe in RouterOS 7" which is not something I can deal with)

All suggestions appreciated.