How about something like this?
https://www.amazon.com/Adapter-100-240V-Transformers-Switching-Adaptor/dp/B019Q3U72M/ref=sr_1_3
or
https://www.amazon.com/FAVOLCANO-100V-Switching-Adapter-Connector/dp/B0111A8U9A/ref=sr_1_9
Not sure the AMPS you need.
Would then just need to make the female plug end of the molex that ties into the adapter.
Also have stuff like this if you already have the power supply.
https://www.amazon.com/JacobsParts-Adapter-Female-Pigtails-Security/dp/B00QJAW9F4