Locking bolt for DV-59 dovetail Model L turret

Looking for a Model L turret locking bolt. The rear "V" base of the turret holds a 5/16" drive Allen type screw that is 5/8" diameter. Screwed into the nose of this Allen screw is a special shaped 5/16" X 24 bolt. The head of this bolt has an angular face with a protrusion on the face that locks into groves cut into the rear of the V bed of my DV-59. This is how the turret is locked into place.

It is that angle head bolt, which threads into the Allen head bolt, that locks the turret in place that I need. New or used. If none available from PM members then any chance on a part number?

Thanks,

Dan Miller

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