There once was a forum member who had heard of a method of bending the wrist of a stock by applying hot oil to it along with some heavy sash weights to apply the force.
He tried it and it did nothing so he got several "heat lamps", coated the wrist with oil and wrapped the wrist with aluminum foil. I think he added some more weight too.
Focusing the lights on the foil he let it really heat up and kept it hot for hours.
When he removed the lamps and foil he found the whole area was charred beyond description.
Seems I recall the stock still hadn't bent but even if it had, it was basically useless in its burned condition.
One option that will cost at least $120 for the lowest grade of Curly Maple is to go to Pecatonica River and buy one of their TC Hawken replacement stocks.
The stock from them has over 1 3/4 more drop at the heel of the butt and the comb has a corresponding drop to it.
http://www.longrifles-pr.com/thompsoncenter.shtml
These are not exactly a "drop in" stock and they will need to be shaped a bit, sanded and finished but they are not nearly as difficult as trying to build your own stock.
IMO, the price is money well spent.
You will end up with a nice shooting rifle made with a classic wood.
Give it some thought.