The base is 4 diameter. Marked on the underside of the ballerina with the Mueller Volkstedt Mark used from 1907 - 1949.
She is wired and working. The cord is old style with a thumb switch, I see no fraying, but you should always have an electrician check it out. The minor issues I observed are. The very top flower is missing a petal on the back side. The second from top row of two flowers, the one on the left is missing a lower petal.
The three flowers at an angle on either side I see no issues. The Ballerina is missing some minor lace to her dress, the flowers on her waist appear to be all intact. She is loose from the base as you can see, but does sit well without any additional adhesive needed, be careful moving her.
One note, the oval area behind the Ballerina, looks like it may have held a photo or a mirror. This item is in the category "Collectibles\Decorative Collectibles\Sculptures & Figurines". The seller is "barnabas094" and is located in this country: US. This item can be shipped worldwide.