Does anyone have any Power Supplies 76-710-1650 for sale?
Are there any companies out there that can repair non working 76-710-1650 power supplies?

I'm sure the used phones repair folks can take care of this.
https://usedphones.com/phone-cell-radio-repair/

I tried them but unfortunately they don't repair the power supplies.

Try these guys: www.azteccap.com
They are Telrad's preferred vendor for repairs.

Thank you