Well first, any Speed Triple 97-10 or Daytona 955 97-06 will work.
... I am told it is an extremely difficult thing to swap frames?
That depends on your skill-set. You are obviously going to have to strip the bike completely as everything is ultimately connected to the frame. One of special tool requirements you will need is the swing-arm spindle nut tools to remove the swinging arm.
I would have to assume that with a bent frame, there has to be substantial other damage? You need to figure out all the parts you need and ultimately whether it makes economic sense. You might be better just parting it out.