Buy a newborn pacifier of your choice.
Cut off the nipple.
Use E6000 glue to glue on a strong earth magnet. You are not going to glue it flat like you do with a magnetic paci for a reborn. You are going to glue it sticking out like shown in the photo below. Let it dry for 48 hours. Some dolls the magnet part of the paci will fit right into the mouth and stay there, for others you might need to add a bit of poster putty to help keep it there. This can be used as a substitute for the bottle.