This is a very fine small and delicate mirror. A related example is illustrated in The Mirror Book, American and English by Herbert F. Schiffer. (See scan below.)
Note the beautiful scrollwork carving that arches the bird, which is further introduced into the lower section of its carved elements. Also note the crimped corners at the edge of each mirror, and these are the details that show the fine work of an inspired artisan. The mirror is original and it’s a little gem.