Replacement temperature knob for a Tefal Superglide 60 Steam Iron FV3161

My neighbour, Stan - a sprightly 94 year old - popped in to see me earlier this week, bringing his iron to see if I could mend it. I'd shown him my new printer, and he was fascinated (as we all are when we first see a printer meticulously extruding another layer). He wondered if my new toy would be able to help.

It seems his wife, Ellen - a mere whippersnapper of 89 - had been a little bit heavy handed with the knob, and it had come off in her hand (I could probably have phrased that a littl