Besides AMK's "For Sale" catalog, or online catalog, you need ANK's "Guide to Ford Fasteners 1955-1973, first published in 1997. While it is mainly bolts, screws, etc., and lacking some on plugs, fasteners, etc., it gives detailed descriptions of most all fasteners used through that period, not just the ones they sell.
Then, having the Part Numbers, check your local Ford Dealer - you'll be surprised what is still available, especially in the rubber plug line ; even with the original Part Numbers molded into them. On bolts, nuts, and other metal items, they may have some, but you'll need to look at them first, as, over the years, the same fastener may have changed the finish in which it is now supplied. Also, don't expect to find any bolts, screws, etc. in 1/8" increments (as Ford was noted for supplying), as these are nit readily available today.
Another good source for bolts, screws, nuts, etc. is McMaster-Carr out of Chicago.
Bob