Hand reaming a stack of fender washers.

With limited thickness a RH spiral RH cut is high probability pulling into the stack, jamming handsomely, because they might be clamped, but not all that parallel - free of gaps.
LH helix, RH cut will do much better.

Depends on volume, then thickness. Make a pair of soft jaws encircling about 80% circumference, 100% depth. They'll clamp just fine.
Alternate can be a bushing, pocketed likewise, with 2 relief cuts and one split in lathe chuck or collet. Plenty quick.
Straight flute step drills are very common, perhaps that is what I should have made clear. I've never seen a left hand spiral step drill. Machining them individually will allow one side to be chamfered by using the lead onto the next size step. Turning them over and using the step as a pilot to locate the bore will also allow chamfering of the other side. These operations can be simply performed freehand in a drill press and hand held vice.
 
Is the end goal a guided die stock? Is that what you're aiming at?
 
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