Hi Nate,
I recently had to bend one "straight". First, I would make darn sure yours is actually bent AND which way. There are other things that could cause it to shoot left, like problems with the muzzle crown or cone, pressure from the wood of the stock or the barrel pins or who knows what else.
Take the barrel out of the stock. Get a long straight-edge, metal yard stick, etc. Lay it along side the right flat and measure the gap at the widest point (dial calipers work well here) This will likely be in the waist of the barrel, since it's the thinnest and most likely area to get bent. Write down the measurement. Measure the opposite (left) flat at the same spot. Are the measurements the same? If so, that plane is straight. Repeat for all 4 sets of flats.
The barrel I had to bend straight was a 38" B weight in 50 cal (thin walls!). With the sights pushed over to the max, it was shooting 8 inches left at 25 yards. The gaps on my 2 flats were .180" on the left flat and .100" on the right flat, if I remember correctly. But it was definitely bent. I called the barrel maker and he suggested straightening, but if I didn't want to or I couldn't get it straight, he offered to replace it. You can't beat that. I would call your barrel maker to discuss your situation.
If you do decide to straighten, I would not clamp the ends of the barrel, as they will want to move. I used a piece of 2" square steel tubing for my base fixture and set a block of oak under each end of the barrel. I used a big C clamp to bend the barrel. You want to push on the flat with the least gap. You won't believe how much you have to bend the barrel, because it will spring back. It's trial and error. Bend a little, measure both flats... repeat until the gaps are as even as you can get them.
Or you could just put in the crotch of a tree and give her a yank.
Good luck.
-Ron