As for Belle's dress look in to what she wears at the theme park and the stage shows, they match the toon a lot better. In general the doll is intended for children so they need to make something that will last, which makes no sense because the outfits in the box o' princesses are shredding if you look at them funny :/ I'm going to have to get a gallon of Fray Check.
Now the time period seems all over the place because Belle's gown looks to be from the mid 1800's with the round skirt and the gathers. I have some glittery tulle in my want to make one, I'd do an underskirt then a gathered transparent overskirt. I've seen some fashion plates of regular gathers like that. Won't go further in to the all over the time line as long as it's through a modern filter Disney look.
And all I can say about BBTS is their shipping can be a smidge much because they pack for Fanboys who never open their toys. My 1/6 Phantom and hi packing materials came in a box a 1/4 or 1/3 doll could have fit in to.