I remember a cotter pin on a J24 disappearing ... but I'm thinking it was not SS and just coroded out and left a little bit of rust stain. got to be real careful with cotter pins. The pin below it is cottered the way most riggers like to do pins so the ends don't catch anything.
There are two sizes of pins used in that box. most originals were 3/8s but my replacement box was 1/2in. on 505 ...
[SS Jib Box Assembly w/ 3/8" or 1/2" Pin: K-10658**D:] The rigging companies generaly use a 1/2 in at the stem and 3/8s at the box ... don't know why that is engineered like that.
just buy one of each and return the one you can't use or take a 99% chance that it's a 3/8 but it does look a bit bigger that the pin directly under it. which should be 3/8s. for the top of the forestay.
re bend ... I've used a c-clamp to "straighten" bent stuff ... bigger clamps are better with say a 2x4 on the straight side to keep that from distorting too much, perhaps on both sides.
related link on halyard box if you haven't had that box out to look at the insides ... it might be something to think about next time you have the mast out.
