Don't buy the arbor press from Stewmac. You can get virtually the same press from Harbor Freight for less than half the money. All you have to do is bore out the ram to accept the caul, and drill and tap a hole for a set screw to hold the caul in.
What do you do about the self leveling caul thing, is that something you could purchase? Or is it not really all that important. I borrowedf a buddies arbor from stewmac, and i really didnt like how the self leveling thing was all over the place, and had to line up perfectly... I just figured that it was necessary.