The only place i know of that sell the sc14 brackets are CRS and you have to buy the whole supercharger kit off them at around $2000. When i put one on my wagon i found a pic of a tracing of the 2 lower brackets. I saved that then printed on A4. Came out the perfect size, I thought i had posted it somewhere on here but cant find it now. But good news is it is somewhere on the World Wide Web.
For the belt if you have air con and want to keep it then go for a ecotec belt but if you dont have air con or dont want air con then just use a aircon belt and dont put it on the air con pully.
For the motor, thicker head gaskets are aways a good idea when playing with boost but not a must, aslong as you get something good done with the tune you should be right with a standard motor.
Now go back through all the threads you have already seen on this topic and read them, after that you shoud know all you will need to know because all the info is on here, so you might even have to use the search button.
Matt