Back in the 1950s ans 60s, breakfast cereal had these prizes of US Presidents and their First Ladies. The Hobby Bunker in Malden, Mass. found the molds and makes reproductions of this series. There are the Lincolns, Washingtons, and actually the best castings, the Eisenhowers.
I was able to buy some rejects and found that the Mamie Eisenhower has potential for conversion. I have to add that modeling skirts takes a lot of modeling material and talent sculpting folds. Even if you remove the arms, you have a great skirt and a well detailed and pretty face to work with. The figure can make female figures for the second half of the 19th Century.
I haven't done anything with the Mary Lincoln figure or the Martha Washington figure as yet.