if you can, try to find a local industrial hardware store near you.
not the regular home improvement hardware stores, but a store
that stocks just about every single bolt that there is, sells em singularly, or in a pack (of 50-100 depending) for a discount.
my store stocked grade 8.8 fasteners and they were only a few cents a piece.
those places a great to have in your arsenal in case you dont have time to wait for a package in the mail
(edit: kinda like fastenal previously mentioned, except my local bolt store was even more affordable than them)