Timber bolts

[DHZIEMAN]

Originally Posted by Licensed to kill

Trying to find 5/16 X 4" timber bolts for the bottom wood on my DD. Can't find them anywhere. Got all excited when i read the thread on the wind wing bolts and someone mentioned "bolt depot" so I checked and they don't have them. I could use carriage bolts or even regular bolts with washers I suppose but would sure like to find timber bolts like the originals. Any thoughts on where to find them? What do others use if timber bolts can't be had?.

Closest thing I could find

Hillman 240114 Carriage Bolt, 5/16 x 4-Inch, Steel, Zinc-Plated, Silver, 50-Pack
It is not flat but is as close as possible.