You can make a homemade casting porcelain doll mould which lets you make as many models of the same doll as you wish. A two-part mould is necessary for doll-making because they can't be removed from a one-part mould. You can use this mould as many times necessary to cast porcelain.
Create a container mould out of small, straight-edged, scrap acrylic pieces. Put the porcelain doll flat on its back on a table. Place four pieces of acrylic together in a rectangular-like fashion around your porcelain doll and add a bottom piece underneath. Position the acrylic pieces so that they leave approximately a quarter-of-an-inch space around the doll.
Glue the acrylic pieces together using a glue gun. Allow to dry. Make sure to apply enough glue to the pieces to make the mould waterproof.
Spread non-hardening clay onto the bottom of the container deep enough to cover the doll up its midline when it will be later embedded in the clay. Check to see that there are no bubbles or holes in the clay.
Embed the doll back-side-down into the clay, but don't push it all the way down to the bottom acrylic piece.
Press eight half-inch holes into the clay around the doll with a pencil, eraser end down.
Pour uncooked rice into the container until it covers the doll by at least an inch. Then pour the rice into a measuring cup. Note the ounces and mix this amount of urethane according to the directions on the label.
Spray the entire inside of the container and its contents with a mould-release spray.
Pour the urethane slowly into the corner of the container and allow it to set for 24 hours.
Remove the acrylic base of the container using a knife to pry it off.
Turn the mould over and remove the clay with the knife.
Spray the inside of the container and its contents with mould-release spray again.
Mix the same amount of urethane as before and pour it slowly into the corner of the container. Allow to set for 24 hours.
Pry off the acrylic sides using a knife and carefully separate the two pieces of the mould.
Measure the two largest sides of your mould and cut two pieces of wood or plastic the same size as the mould. Sandwich the mould between the two cut pieces. Hold the mould and wood or plastic together with some rubber bands. It's now ready to pour casting material into the mould.
Don't pour urethane directly onto the doll because this could cause bubbles in the urethane, ruining the mould.