Welcome !! There is a very common problem with the SVX and power steering. It is not usually the pump, but I don't know what the real problem is on this car. There is an O ring that goes bad, and when this happens, gives all indications that it is a bad pump, but if the O ring is replaced, it usually fixes the problem. There are directions on how to do this easy fix in a locker called How To. Here is a link to it. Good luck and again, welcome to the forum.
http://www.subaru-svx.net/photos/user.php?How-To