First off, that's a dumb board, so there's nothing to prevent you from replacing it, no logic on the board. However, unless the board is burnt badly, you can simply replace the resistor with an 8 ohm one and then fix whatever is preventing the resistor from getting power. Replacing the smoke unit will be a lot more work than fixing a simple problem with the one you have.
Some close-up pictures of both sides of the smoke PCB would help us help you, I don't have one of that particular model to look at.
