I bought the wrong size for me as I rebuilt a little differently, and should have bought 3 1/2" long bolts. 3" might work for you.
I have 8 3"x1/2" and 8 3"x3/8" bolts, all flat head slotted fully threaded 18-8 stainless steel. All brand new from Fastenal.
See https://www.fastenal.com/product/fasten ... tion=Grade
Currently in Mexico, but will be heading back to the US in about 2 weeks and will ship from California. So if you are interested, let me know soon. Otherwise I will leave them on the boat.
Make offers. Discount will depend on how many you want.