Hi Freddy M.
OK, assuming the part is availalbe. If its cost is too high, of course, I'd consider replacing the printer - a shame as it has worked well.
It worked perfectly, although the contacts had looked perfectly clean and nothing to speak of came off on the swabs (cotton-buds on this side of The Pond). Very many thanks. A lesson learned!
I've received a "you have not responded" message (twice). As you can see, I have. Your advice was spot-on and I posted a big smiley for you. Thanks again - I should etch "RFM" on my brow!