Hi Chris this post may come a bit too late but you can find extension cables at:
Is there anything available like this in the US?
Finally checked the cables and yes… I got the wrong ones 
Off to some soldering then 
PS: Because it goes hand in hand with extending the feeder cables, external rfid readers are now possible: How to extend RFID coils? - #22 by trohn_javolta
https://www.aliexpress.us/item/3256812024604440.html?gatewayAdapt=glo2usa4itemAdapt
Amazon US is cheaper but has a longer shipping time