OK, I was not able to find the exact information on these servos. But the SGM are older models. You need to identify if they are absolute or incremental encoders.
You may be able to use the SGDA Servo Drives. Check Ebay, Sometimes you can find them new, at a low cost. The Speed/Torque versions are usually low in cost but require +-10V for control.( More Complicated)
The easier option is to find SGDA position drive. The A models are 200V, the B are 100V.
Please see attached manual.
https://www.yaskawa.com/delegate/get...E-S800-15C.pdf
Please post photos of the motor, wires and the connectors, its quite possible that they use incremental encoders.
To make connection easy, You will need the TA36P terminals, SIGMA Win Software or Keypad programmer, and servo power and encoder cables.
Make sure that if you get the TA36P that it has the cable included.
Iron Man