Well, depending on the location of the frame damage, you could try and maybe straighten it and then reinforce it with some 1" pipe (essentially making a solid steel sleeve by cutting the pipe in half, slipping it over the frame and welding it back together. The better solution would be to replace the frame (roughly $500 and 10 hours of labor or so by a shop). The money and time could be more or less, depending on where you get the frame and where you get it installed if you go that route.