All of these items can easily be created with artwork found online or on a computer. The average person should be able to locate all of the images needed to create such artwork in a few minutes and simply use Clipart to include them in their document.
The easiest stamp to make from a manufacturing point of view is one where the artwork has a line thickness that does not fall below the minimum required. The minimum line thickness that is recommended is 0.2mm (0.00787 inch or 0.57 point), if it does fall below this, the 'wall strength' of that part of the stamp is compromised and may become distorted. Having said this, you can convert an image with fine lines to one suitable for stamp making.
So watch for this all month; you'll be amazed. Imagine each invite without the Christmas clipart and ask yourself, "how would this fine piece of paper look without the reindeer poking out its head, or the mini Santa graphics in the bottom corner?" Christmas clipart is a big supporter of the holiday spirit, because without it we would all be monochrome and unhappy.