Tack Room Inc., Big Dee's, Adams Horse and Pet Supply (in Maine) and of course Smartpak are my choices - I have ordered from all of them and the longest it took for the stuff to arrive at my office was two days . Most offer free shipping too though Big Dee's has some stuff that is FOB.
"When a horse greets you with a nicker & regards you with a large & liquid eye, the question of where you want to be & what you want to do has been answered."CANTER New England
I think it depends on where you live. I almost always order from Jeffers and get it within 2 days, standard shipping. They're in GA and I'm in NC. Their customer service is outstanding. Love Smart-Pak too.