I've tried to search for the connector in Amayama but only see a whole loom of wires hahaha. Anyone knows if this is some standard Molex-ish connectors i can buy and replace it myself? Thanks in advance.

If it's the 5 pin connector, it should be this part number: 90980-12292
Something like this (or wherever you want to get it from):
​​​​​https://www.toyotapartsdeal.com/oem/...980-12292.html

Thanks. I also put in an order for the 90 deg back cover part number 82821-50500(part number courtesy from the IS F forum section).