I tried to get on USPS site and from what i can tell it will not be over $10.00. My zip code is 29708 - Fort Mill, SC. It weighs around one pound the box size will be a little over 15 inches all around 15x15. I hope this helps!
You weigh it and then you put your zip code in, versus the other persons. and you also need a rough idea of the size of the package. You have several options for mailing--first class, priority mail, etc. I think flat rate priority mail would be very reasonable for both-10.50 or something like that. One doll is a bit more complicated. They have the box sizes at USPS.com. Good luck!