For example: Agilent E4440A or Anritsu 68369
Keysight / Agilent Ovenized Oscillatrors
Keysight / Agilent 10811A
Ovenized Crystal Quartz Oscillator OSC 10MHZ
Manufacturer: Keysight / Agilent
Keysight / Agilent 1813-1899
Ovenized Crystal Oscillator Assembly, 10 MHz
Manufacturer: Keysight / Agilent