Thanks very much to everyone who's posted, nice to know I've got off to a good start.
I actually took the pattern off a metal key-rack that we bought about 15 years ago in England.
I just scribed round it and took it from there.
I don't know if there would be an issue with copyright, but I'd gladly post the pattern if anyone wants it.
It's just a scribing, as I said, and after I'd turned it into a jpeg, it's not on a very clean background, but the cutting line is well delineated.
I realised afterwards that I should have used a colour other than black when I traced it, to make it easier to see when cutting.