Contact HOB and get a new one!
Just checked the HOB site... they ARE bringing back the P-47.. $60.00 for the kit.
I have a similar problem with a different canopy. I thought about doing what you suggest but learned from another modeler whose experience was "it doesn't work." That's as far as I got. You can get another canopy.
Yea, basically if you don't have the mold, heating will only result in bigger problems.
Try using a hair dryer set on maximum temperature. You might restrict the air inlet to raise the temp a little more but there is a risk of damaging the dryer. Since the canopy is essentially not usable, you don't have a lot to lose. This method will all but eliminate the whitish marks that result when a canopy is bent.
An alternative would be to put the canopy in boiling water for a few seconds or so to see if that causes the bent areas to return to the correct shape.
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