I finally busted out my short steel beginners bending kit from Short Steel Bending. I think I actually requested these over a year ago, but then chickened out trying to use them for fear of wrecking my hands.
Upon reacquainting myself with the kit, I found 3 bars marked 120 pounds and 3 bars marked 140 pounds. Both appeared to be 3/16" cold rolled steel, but the lengths were different.
After a couple of attempts wrapping with the Cordura wraps, they felt reasonably secure.
I tried double overhand, then underhand, and finally could get a kink with a reverse grip bracing with my left hand and moving my right hand. On the 6 inch stock, I could sweep this way as well and then did a two handed crush. On the 5 inch stock, I switched to a double overhand for the sweep and then was able to crush it as well.
120 lbs - 3/16" by 6 inch success - Reverse Grip
140 lbs - 3/16" by 5 inch success - Reverse Grip, switch to overhand, switch to underhand
I would like to throw this in on a regular basis and have some stock on hand to play with. After exhausting my beginners kit, I will probably order 30 pieces of 3/16" cold rolled steel (20x6"; 10x5.5") from FBBC for $21 plus shipping.
Short Steel Bending sells 10-packs of rod stock in various lengths and diameters for a $20 plus $10 flat rate shipping.
Fat Bastard Barbell Company sells 10 packs and price is based on diameter. Not sure what shipping costs.
Eat Chalk Get Big has limited stock and is pricier at 5/16" 10 pack 7 inch lengths costing $30 plus shipping.