Based on this product's specifications, here are some alternatives and similar models
Power Supply MITEL RFP 35/43 IP (International) – replacement power adapter for RFP 35/43 IP models
Summary description:
Replacement power supply for MITEL RFP 35/43 IP series. This international network adapter is designed to provide the required mains power to RFP 35 and RFP 43 IP devices from MITEL. It serves as a direct replacement for the OEM adapter, ensuring stable power delivery for voice-over-IP base stations and cordless system components in office or enterprise installations.