I don't think you can copy paste a text element since you can't create object with ArcPy.mapping. However, you can create a pool of text elements outside of yourt page layout (on the margin), and cursor through them and move them where ever you want to on your layout page. This is how I've been creating dynamic tables using ArcPy.mapping i.e. by using text elements (white background and border line), populate them, for each data driven page. Hope this helps.