I also have a stratum 1 NTP server, it is on 44.13.151.3 (ntp.g1fef.ampr.org) and it is open to 44/8
It’s a Symmetricom S200 with Rubidium clock and GPS and is located in the UK for anyone in Europe it would be better choice than the US based clocks.
For people who want an easy stratum 1 server and don't have money for such gear, have a look at the LeoNTP. It is made by a UK radio amateur and it is a GPS locked NTP server in a very small package. It costs "only" 300 pounds (about $400). We have considered it for repeaters but unfortunately it cannot provide 10 MHz and 1PPS at the same time, which we do require.
Rob