I'll fill the inside with crushed tissue, overwrap with more tissue and then some bubblewrap.
Without the glass inside, which I decided was better, it weighs less than 2 ounces. So it would ship first class, in a 10 X 10 X 7 box for $3.25 but I'll probably go for Priority at $3.85. Bigger box and faster shipping. Plus some "weight room" for light cardboard to be sure it stays in shape.
Lucy
P.S. Good looking pics in the other thread. Your daughter is a princess!