Made this banjo bridge for a 5 String Banjo. Haven't had a chance to test it out yet, but I'm going to try to print @ 2 shell layer and 100% infill. Est. @ 20 Min. No Slots so you can put your own in. Let me know if it works for you.

This was made in Inventor Fusion while flying from Pittsburgh to Pheonix. Dimensions were take from aforementioned website/image.

http://behindthetone.com/johnfisher/banjo/bridge/brid.htm