I was thinking all the way through with a carriage bolt. Just don't know if they come in metric since they are kinda old school.I can get anything at our local hardware store, if you just want to center bore the handle. I probably want to go pretty deep, since it's wood.
Well, here they are. Whadda ya know?
Maybe hard to find the size you need?
M10-1.5 X 30mm Carriage Bolts/Partially Threaded / A4 Stainless Steel (Quantity: 400 pcs): Amazon.com: Industrial & Scientific
M10-1.5 X 30mm Carriage Bolts/Partially Threaded / A4 Stainless Steel (Quantity: 400 pcs): Amazon.com: Industrial & Scientific
smile.amazon.com