Rather than West Marine, who is really an "everything store" for boats, or even the local discount hardware chain... is there not a good hardware source around?
I have used these guys for well over 25 years for all my serious hardware needs. I have spec'd hardware for military projects through them, and have gotten exactly what I need and at a decent price.
http://www.westernfastener.com/
The only disadvantage is that there is a minimum purchase... But I usually found enough hardware requirements to fill that minimum, easily.
If the proper hardware is what it takes... Western Fastener is where I go. Surely there are other similar no BS hardware distributors around... that don't tack on extra fees just for the "marine" market.
BTW I have no association with Western Fastener in any way, other than personal satisfaction.