Simplicity 8064, in Heather Ross Briar Rose Cricket Clover. Size four.
This pattern should be straightforward, but even by big three patternmaker standards, it's a little rough. If you follow the directions as written, you will sew the elastic casing opening closed before you insert the elastic. It could have used a copy editor. Armed with that knowledge, it's not a bad pattern.
I made the straps adjustable by adding buttonholes to the straps and buttons inside the dress.