How do I get / add graphics to the existing library in Elements 14

There are a number of great graphics to choose from in the existing graphics toolbox.  However, I'm trying to do more for wedding save the dates and post cards.  I would like to get some laurels and wreaths to add to the pallet to select from.  So, a couple of questions:

Where can i find additional fancy laurels and/or wreaths that could be used in Elements 14?

Once i find them/purchase them, how would I go about adding them to the existing graphics library so they are always available to me?

Thanks,

Martin