Find a bolt that threads in easily (fine thread is what I think they use) and then take to hardware store and pick out a SS screw in the proper size and head design (Phillips oval head) and thread pitch
410 ss is the one that lightly rusts just make sure if you buy at any store that it’s 304 or 316. Our ace hardware only carries 304ss products (probably for that exact reason). Fastenal is a great idea as they have a much larger selection
All the ACEs around me are all but useless. The stuff HD/Lowe’s sells is mostly unlabeled. Haven’t checked with a magnet but I would guess it is some ferritic 400 series nonsense. I found a carbon screw that fits it’s just a little long. I’m going to visit fastenal and get something about 1/8 shorter in 316L.
I ended up getting a 5 pack of #8-32 x 1" SS screws at HD. They wouldn't stick to a magnet so I'm hoping they are 300 series. The carbon screws I found in my garage were corroded from 1 day of being in there. I just need it to work long enough for my daughter to lose interest anyway.