Polaroid SLR 680 Film Camera Not Working

The viewfinder is black and something is loose inside the camera. The vulcanite has deteriorated. When tested with film the camera powers on, the flash light turns on. The lens seems to focus when the shutter is half-pressed but since the viewfinder is black is hard to see what it’s focusing on. No further testing has been done. The camera doesn’t seem to be fully closing; there’s a small gap.