Hi Lofty, here's an update; I've had no reply from the seller in Portugal. I really can't be doing with procrastinators, so I've given up on him, which is possibly a mistake as I once did the same with a seller in Spain and he replied 2 weeks later.
Moving on, after more searching for something similar to your carbon sticky tape, I came across this for the sills
https://www.ebay.co.uk/itm/251280218491 ... qCEALw_wcB
As you'll see, it comes in different colour and widths, so I messaged the seller to ask it it would follow the contours of the door sill as our sills are like a double sill. They assure me that it will, although they did suggest that vinyl tape would do the job, but I fancied the blue colour so I've ordered a length of 60mm X 1000mm to see how it goes. It was only £6, so not much lost if it doesn't work. I'm dubious about my applications skills as I always seem to mess up with sticky stuff !
If it works I will order more because I've only ordered enough for one sill.
Because this will be a relatively cheap solution if it works, against my better judgement (pricewise) I've ordered a stainless bumper guard .
https://www.ebay.co.uk/itm/373542554224 ... %3A2334524
They come in both shiny and brushed steel (I opted for brushed) and the reason I went for this is because it has a lip that goes over the rearmost edge of the bumper and offers better protection than those that just stick on top of the bumper - I hope.
I'll let you know if they've worked after they arrive.