Sounds like more of a dent than a bend. I would think that anyone skilled in automotive dent repair could easily fix the dent. Once they got it really close, you could add some extra insurance by having the head tube reamed back to a perfect circle.

Alternatively, you could just try to press the headset cups in and let them do the straightening. Chances are if the lead-in on the cups will allow them to get started, they'll press in and stay in just fine.

If you wanted to try something yourself, this might do the trick if it would fit: http://www.thetoolwarehouse.net/shop/LIS-32500.html