On the Android app it's Menu -> Freenow Loyalty... Ken. Then if you scroll down, under Gold, you should see 10% off Vehicle Components. (6% for bronze, 8% for silver)... click on that and your discount code is there. I haven't read the T&Cs so I wouldn't screenshot it or anything like that, I assume it's intended for your personal use... but sure we could always say I ordered a bit for you or something if questions were asked!
I'm not going to bother ordering the pump for the Yaris unless it fails again, anyway. My thinking is that the way it failed wasn't critical so should the once new one fail in a similar way going forward there'd be no great rush to replace it. It seems that the actual fault with the pump was with it's integral speed sensor. A quick look at the partially drained reservoir bottle revealed that coolant was circulating prior to disassembly and a bench test comparison between the faulty one and the once new one concluded no noticeable (by ear / feel) difference in the actual speed of rotation. Further testing revealed full continuity from all relevant connecting cables to the relevant connections on the power supply ECU / fuse/relay box so the fault had to be either in the power supply ECU or (as seems to be the case) the sensor within the pump. Hence I've drawn a line under it as adequately repaired regardless of using a 2nd hand component.
Just for reference (as I know a lot of you drive hybrids) the symptoms in this case were an orange engine management light and an orange check EV system light being constantly shown on the dashboard together with the EV Mode and Eco Mode options being disabled and the cruise control system being disabled. I don't think the younger not so young lad noticed anything other than the lights but in addition to the disabled systems it was also evident that the car stopped using it's EV mode almost immediately after moving off so was (presumably) using more petrol than normal as well. The fault code given by my OBDeleven (now licensed by Toyota as well as VAG and BMW) was P314A - Inverter Coolant Pump Speed Signal.