replacing the logic board for black screen of death.

I am looking at replacing the logic board for my Note 2 . however my carrier At&T boards seem to be out of stock or very expensive like 3 times more that sprint or verizon. I would like to know if I can use one of these boards and just unlock it to be able to use any simcard. ??? Is this correct ? I am not really familiar with working on cell phones and greatly appreciate any assistance available.

I am not sure but the new board should have its own Imei code. ( is this correct) ?