The BladeForums.com 2024 Traditional Knife is available! Price is $250 ea (shipped within CONUS).
Order here: https://www.bladeforums.com/help/2024-traditional/
If you intend to keep the slotted portion in tact, I'd probably just cut the head down and re-slot it with a slitting saw or even a dremel cut-off wheel. You might also look at something like a cheese head (or cheese round) screw for the mail side, though I'm not sure I've seen them in a female configuration, specifically.
Pop's knife supply has 5/16" but pretty sure you will have to modify length and cut slot.
Pop's has 5/16 slotted Corby bolts with a 3/16 high head portion. I use this shorter version all the time. Excellent quality also.