Program PCM/ECM '99 Accord

I am planning to replace the PCM in a '99 Accord 4cyl, it's giving off the code P0685, I verified no mouse nests or disfigured wires, so I assumed the PCM is to blame. From what I've read, it looks like changing the computer is easy, but it'll need to be programmed to match the immobilizer. Am I stuck with the dealer here, or does anyone know of anywhere else local (SE MN) who can do it? Thanks!

And if anyone has any input, I'm all ears. I can get a used PCM for about $50, so reasonably cheap for sure.