I had a double mastectomy this past April and my drains were in for about 3 weeks. I just pinned the drain to a pocket or inside of a shirt. I am not sure how the first purse item would work. But the belt idea would work, but they would need to be given to the woman at the surgeon's office (to be taken to the hospital) or given upon release at the hospital.
I agree with Maria B. It would be something I would get rid of once the drains are pulled. It's easier to put that out of your mind with the fewer reminders left around. So one should not go to a great deal of expense or detail in making them.