For posterity... by my measurements, this is the appropriate bolt;
AN5-7 is the normal tolerance bolt, you can undersize and ream to match
or
NAS6205-8D
is the close tolerance equivalent.
A/S doesn't sell the "D" (drilled) version so you'll have to drill it.
Do you need a castle nut? I thought that those were only for pieces that moved? I can't remember what I used, but I am certain that it what was called out for on the plans.