Banks always have broken, beat up, pen sets on their desks. When they get too bad they put them in their store room, stock room or on a shelf somewhere. Get to know a banker and ask them to show you their stock room. Always check the old buildings, not the new ones.
Far fectched, but what the heck. It might work. Of course when you ask a banker to see their stock room, they think you are casing out the place so this might be more difficult than it is worth while.