nrp,
Try gen-aircraft-hardware.com or give them a call.
There are lots of places in S. Cal. that sell aircraft quality
hardware. You need to find out exactly which NAS and MS bolts you need
and then do a google search. I have done this in the past and found
several suppliers of say, NAS 8703 stainless countersunk bolts for
Lance fuel tank screws. You realize that there are hundreds of
different NAS and MS bolts available, all the way up to 260,000 psi
tensile strength, corrosion resistant, 1200 degree F, etc. Some
designations are merely 1/64 or 1/32 oversize of a certain other NAS
or MS number.

regards,
Bruce Cunningham
N30464 C177A