Hi this Mandolin Banjo is very old and it is very well made. I don't know much about it but my family has had it for at least 50 years. This  was sent to a Luthier at one point. They installed a new head strings and a bridge and repaired one of the tuners and knob.Please see photos the repair did not hold and  it will need a new tuning machine. This is being sold as a project all of the other tuning machines work do work . The one that is broken broke off at the stem and the knob is also split. The tuner does work when you rotate it though it is just broke where it  interfaces the knob.You can find used Weymann tuning machines for these or perhaps update it with a new one? That is up to you. This will also would be great for parts I would love for it to go to a good home.