well you could buy some plaster of Paris and make another casting depending on what exactly the mold is made of you may be able to do a resin casting but that would be more iffy you could do a silicone casting for sure so there are uses but I'd assume you'd have to stick with that original mold I can't think of a safe way of breaking it down to make another mold
Is the molding material cold? My reason for asking is my sister has cancer and is going through chemo. I want this as a keepsake peace. Due to her chemo she is ultra sensitive to cold and if the molding material is cold she will not be able to do this.