Thank you, all who commented that Mr. K would remember me if I sent him a well-worn t-shirt of mine. Above, he is sleeping on the t-shirt, which arrived today. R says that when she opened it up and put it on his bed, he went over to it and took his signature looooooooong sniffs of joy, while wagging his tail furiously. And now, she says, it is already his favourite thing.
Picture me smiling!