Alas this planned mold of Ruby and Chomper has still not been made. John sent me the Ruby shoe charm back then and I'm really grateful for this. But unfortunately there was a drop of glue on this Ruby which doesn't infringe the looks of this figure in its original function as a shoe charm, but does make it impossible to make a good tin mold from it
This is an image of the figure with the glue on her tail:

Unfortunately I have been unable to remove that glue. Since it is the kind that would allow for this figure to stand the special force impossed upon it in its function as a shoe charm it seems to be a kind that so tightly connects with the rubber the figure is made of that it seems to be impossible to separate the two. In a mold that glue would create a bumb destroying some detail of the figure and posing a serious flaw in all tin figures made from that mold.
So I was quite happy when recently I found on ebay a German seller offering land before time shoe charms including Ruby. I bought two Rubies and well, this is what I got:

Smaller, much less detailed, a lot less clear shapped as the original Jibbitz shoe charm this one is totally of limits to be used for the purpose of mold making.
Ruby seems to be less available than the shoe charms of the five original characters. She is not currently offered at ebay either. I do hope to ultimately find a figure which (along with Chomper) I can turn into a mold.