Most is 1 3/8", with some other sizes thrown in. All mild steel. There are some nice wide bar stock pieces for header flanges, too.
I don't check PMs or the forum much, email me at filmaynard at gmail d0t c0m.
$100 shipped east of the Mississippi, $110 between there and the Rockies, and $125 to the West Coast.
I might flex on the price if you show me photos of a rockin' project car in progress.