Since I can't post in original thread here:
https://community.plus.net/t5/Everything-else/Looking-to-extend-power-supply-of-my-router-but-DC-con...
I'm adding this for those still looking.
Found this cable which could be of help to someone, since I power all of my devices requiring 5V and 12V power supply off of my server.
https://www.ebay.co.uk/itm/5-5mm-x-2-1mm-to-5-0mm-x-3-0mm-DC-POWER-ADAPTER-CABLE-SAMSUNG-CENTRE-PIN-...