I use it on an EdgeRouter Lite 3 which is about $99. See:
https://github.com/Lochnair/vyatta-wireguard
https://community.ubnt.com/t5/EdgeRouter/Release-WireGuard-f... (discussion)
https://github.com/Lochnair/vyatta-wireguard
https://community.ubnt.com/t5/EdgeRouter/Release-WireGuard-f... (discussion)