You can buy replacement connectors at Digikey.com
Specific links are below:
- 4 PIN Connector”https://www.digikey.com/product-detail/en/on-shore-technology-inc/EDZ950-4/ED1719-ND/123871″
- 5 PIN Connector “https://www.digikey.com/product-detail/en/on-shore-technology-inc/EDZ950-5/ED1720-ND/123903”