From our stock of used satellite equipment we have a tested and guaranteed NJT5669 C-Band Block up Converter (BUC).
This is a standard C-Band frequency BUC: 5.85 GHz to 6.425 GHz  requiring L-Band input and 24VDC power, supplied via the IF signal cable.
This design features low power consumption, small size and an LED indicator. Type N Female input and CPR137 output flange. These rugged BUCs are installed on thousands of VSAT sites throughout the world.
New Japan Radio Data Sheet