The reverse looks like a dragon-and-phoenix design to me, or at least a dragon, so I assume it's a charm rather than an official coin (though in the Ming period, there does seem to have been some blurring of the line between these two classes of items).
I'm not seeing any Wan Li Tong Bao dragon charms listed on zeno.ru, so it's not a mass-produced or modern charm. I suppose it could be a genuine Wan Li coin that someone has carefully carved a dragon onto the reverse.
The characters "wan li" literally mean "ten thousand years", so it is a fitting inscription for a longevity charm. There was a Ming Dynasty era popular saying, regarding another lucky charm type, that "If a family has a zheng de coin, they will have fortune and honour for ten thousand years".
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis