Have you tried Rena at Barkingdogclothes? She might be able to create something for you. She ships really fast so you might have it in time for your baby's special day.
http://www.barkindogclothes.com/
If you had more time, I would recommend Des at GoFetch. She makes the cutest vests and offers monogramming also.
http://www.mygofetch.com/