I would smoke them all at the same time, ham above the turkey. At the end of the smoking period you could consider moving the turkey breasts into your house oven to complete the cooking there and leave the ham in your smoker. If the ham is not a raw or "fresh" ham and you're only adding smoke to it for added flavor, it will be content to ride it out in the smoker.
3 hours of smoke time will most likely be enough for all of the meat as poultry is a smoke sponge. Open the vent 100% open.