Dorman part number 610-446.1 from Autozone.
They are 1.5 inches long and have the correct press shoulder size for the OE 8.25 axle flanges. (.662 at the serrated shoulder) and 1/2 x 20 thread.
One of our local group has a press and we used that to put them in.
They give me about 3/4 of an inch of threads for the lug nuts after the rotor and wheel are on.