All devices in the 2G System use the same format of power supply:
DO NOT use a power supply greater than 5 Volts. Doing so will cause irreparable damage to the unit.
Power supplies with these specifications can be found at any electronics retailer that sells power supplies.
Example Power Supply: https://www.digikey.com/product-detail/en/phihong-usa/AA10A-050A-R/993-AA10A-050A-R-ND/11203820