When I got my Oppo Find X5 Pro it came with a Supervooc 80w charger, and an 1m cable. 

I want to get a longer cable, but having trouble finding something that is definitely compatible with the supervooc charger (i.e. has the same charge speed).

All PBTech has is this one: https://www.pbtech.co.nz/product/CABOPL00009/OnePlus-USB-C-to-USB-A-Cable---1m-SUPERVOOC---VOOC which is 1m long. 

Am I dreaming in finding a >1.5m cable that will work on the supervooc charger I have?

Alternatively, is there another type of charger (and compatible cable) that I could look to, that can charge my phone at the same speed?

(It may be obvious by now that I don't fully understand the different power specs of chargers and cables - and the answer might be really obvious to you, but not for me!)