If you're a purest then the original rivets were 3/16" brazer head semi-tubular rivets with a 13/32" head diameter.
McMaster does not have semi-tubular rivets, Byler Rivet is all pop or blind rivets, Big Flats has some rivets that are close or that you might be able to modify and get by with. Jay-Cee Sales
http://www.rivetsinstock.com/rivet22.htm has semi-tubular 3/16" with a Truss head diameter of 3/8" that are about as close to the original rivet as your going to find.
The brazer head has a shallow radius and tapers to a sharp edge, the truss head has a shallow radius and has a small shoulder at the edge. You can put the truss head in a lathe or drill press and file or sand the shoulder away and it will be very close to the original brazer head rivet.
The only draw back to buying from Jay-Cee is you have a minimum order which will be enough rivets to do several hundred AD trucks. And you will need to buy the setting tools for the 3/16" semi-tubular rivets. The proper way to install these would be with a rivet squeezer. Hand squeezers are avalable from Jay-Cee (not cheap) and as you noted, setting the rivets by hand with a hammer will most likely bend something.
Denny Graham
Sandwich, IL
