I'd say if you're gonna go for this, go all the way with a custom jobber rather than Fredricks or some such. There's no substitute for a *real*, sturdy, can-do-the-task easily garment, and it needs to be made to fit the woman, not the other way around. Expect to spend around $400+, depending on style, fabric, bells & whistles (!).
If you are inclined to spend the money and go this route, I recommend (for the non-*ahem*-specialty route):
Darkgarden <br>
Meschantes <br>
The Other Woman