Thanks to Neil and everyone else who offered ideas.
I thought you might like to know how the Aristocrat badge, for my Sheerline, has turned out.
The easiest way was, in the end, to just rub-down (lightly) the badge (that Neil found for me) and then use chrome paint to bring it back to its former glory.
I'm exceptionally pleased with the outcome. Not as 'original' as re-chroming I know, but I hope you think it's OK too.
I've attached a few .jpg images for you to look at.
I've also created a 3D printer image file (in .stl format). If you would like me to send a copy, please, just ask.