ModelBuilder,
Be carefil with that Miliput! I had used it many times and actually liked it a lot. This time it never, ever, never, cured. But, I will say it was probably old in the box (from Hobby Lobby!) Just make sure it seems pliable and kneads easily, mixes well.
Unless they sell real small boxes that I've never seen- you'll have more than enough!
Welcome to the GB!