I need a few elevators bolts in the 3 3/4" to 4" range. Every place
I've found on-line seems to carry a max length of 3". I've tried
McFeely's, Graingers, McMaster-Carr, and few other web sites.

A local Fastenal store says that can get them for me, but only in lots
of 50. At least that tells me that they exist.

Short of calling every company that lists a 3" bolt to see if they can
get longer ones, does any know of a source that I can go directly
to?

Thanks!