I've posted 2 lists here that came from BMC to the dealers, one covers nuts, bolts, washers and the like, the other is on split pins.
We often mention a particular (Tensile) Grade of Fastener. Most on the Mini are Grade 5, however, others are used, and higher tensile strength is not always best. Likewise, a high degree of caution is needed is contemplating using Stainless Fasteners as they have next to no Tensile Strength, generally, less than Grade 2.
This chart may help with Set Screws and Bolts;-
and this one for Nuts;-
Be aware here that Nyloc Nuts are generally Grade 3 or at best, Grade 5.
I've mentioned above 'Bolts' and 'Set Screws'. A Bolt generally has only around 1 to 1-1/4" of Thread on it, with the rest of the shank plain. A Set Screw on the other hand has the Thread going all the way to the Head of the Fastener.
This chart will help when comparing Imperial Fasteners to Metric types;-
The old method of Specifying Tensile Grades was to use a letter, here's a chart to help with that;-
Some fasteners in our Minis are specified by this method, eg, most of our Head Studs.
As is the case with everything in life, nothing is straightforward !
Spring Washer too come in different Grades (Ball Joint manufacturers please take note !!)
Most Spring Washers in our Minis are either Medium, Medium-Heavy and are few Heavy Grade.
This one is for when doing certain custom work and you need those odd-ball fasteners. Sorry, I don't know a suppler for these, but at least with a chart, you can always point and grunt !