It's probably not the prisms that are out of line, but the barrels themselves. The alignment of the barrels is called "collimation" IIRC, and they can be re-collimated. I had this done on an old pair of fairly cheap binoculars a few years ago by a local camera repair facility, and it seemed to work quite well. The repair guy warned me that they were liable to get out of whack again quite easily, but they seemed to hold their alignment well. I'd call around to a few local businesses if I were you.
John