I’m after some rubber trim, the same profile as is fitted to the rubber lined/steel P clips, I.e. it wraps around a strip of metal on both edges

No idea what to search for on eBay etc though, I just get lots of the standard ‘single sided’ U trim.

Any ideas?

I cant help with the rubber trim but can you slide heat shrink over the metal and shrink it on
Graham

Look up hose clip protective sleeve

Have a look on the Woolies web site https://www.woolies-trim.co.uk/ they seem to have most types of trim

Or even a thin wall bit of plastic hose?
If using heat shrink, 2-3 layers would be best to give protection.