I searched high and low and finally settled on these 2 pieces. They won't be exact as I wanted but the scale is so small I'm sure it won't be too noticeable. I was concerned that the small stand with the smallest cake on it. It's slightly taller than the stand with the macaroons. But I just couldn't find something tall enough.
a little under 30mm diameter
And I'm going to make the flat silver plate out of a button or something I find. Maybe clay covered in silver paint.
Both ebay purchases.