One idea to get your length that you need for your fasteners is to go to a harware store and ask for Binding Post Screws. Fastenal.com has them and there is likely a fastenal near you. you can get them in stainless, brass, and regular steel zinc. Various diameters and lenghts. Fastenal can be a bit on the high side and they only sell in bulk, probably 100 pcs at a time. But if you sweet talk them they may give you a discount.
Hope this helps
Otis