MDL- T'is an interesting piece, but one I'd steer clear from (especially at it's current bid of $1051.99). The dial is off, and not a very good redial in my opinion (lots of flaws); bezel insert is making me scratch my head, the case back is wrong, and of course, the movement is incorrect for a 5513 anyways. I think you'd be better of converting an MBW 1680 into a Tudor, or a 5513; It would cost less to do such a project, and you'd have essentially the same thing once it's done (An ETA based Sub).
Just my $0.02...