hmm, how badly damaged is the PCB? You could probably repair it as long as he controller works.
That said the 84 layout (75% + fn keys) isn't super common. I'm not as well up on current developments so that might have changed. You might be better served by getting a 75% and the function keys on the number row, depends on how much you use fn keys I guess.
switches, etc can all be changed pretty easily, you could harvest the ones you had off the old board and use them on the new one, even recoup some loss by reselling the ones that came with the "new" board.