try the ginger style by 7...wider leg/thigh and higher waist that is smaller...try that one in a 30...

if you want thigh circumfrence to be between 20-22 inches...I would def. say a 31 or 32 in 7's would do the trick...then have the waist taken in becaue if you are a 2-6 they are going to fall off of you at the waist.