Don't make the mistake I did and get tempted by the cheap prices of ebay seller "mycloak", trading under the name "Von Lancelot".. the "corset" I recieved is unwearable - it's a style that has a collar/shoulders attached and it's physically impossible to wear - if the corset is on your waist, the shirt collar is up around your ears.. and if you put the shoulders where they ought to be, the corset is way below the hip line.
What I think they have done is when the scaled up the pattern for larger sizes, they scaled up everything - including the height of the shoulders/collar/top of the corset. The result is not a garment I can use without significant alteration.
The seller ignored my messages and didn't deal with the problems I had at all. Just kept my money.
After I had bought it I found out they have actually ripped off someone else's design, too.

For the real deal, the person to go to for this particular style is "Damsel in this Dress"
http://www.damseldress.com/ . It's what I heartily wish I'd done!