With just a quick search the closest I found was this Simplicity Pattern:

http://www.simplicity.com/p-1539-misses-men-costumes.aspx

At first glance it looks completely off because of the context, but it
really only needs an adjustment to the shape of the pocket flaps (Tonk's
entire pocket is on the outside, not just the flap, but if you are just
going for close and not perfect, just adding the curves to the pocket flap
gets the point across). And you don't need the sleeve cuffs. And of course
you'll put the Tonks style embellishments on it, not the ones on the
pattern. The sleeves in this pattern might puff a bit more at the shoulder,
but it also might just be the way the coat is lying on the model. It's hard
to tell if the collar has a sharper point or not because the pattern is
buttoned up and Tonks has hers open, but that is also a minor detail that
won't throw off the look.

Make sure to post photos when you're done!

~Dianne


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