harmonic balancer just walked into water pump pulley!

[torque2]

My '83 300D (w/ 105,000 miles) harmonic balancer started throwing sparks rubbing against the water pump pulley and appeared to have walked forward. After pulling the fan and wp pulley I found the crank bolt, 3 washers and 3 small metal pieces that when combined could make a pin shape. My ac compressor made some scary noise before it happened, so I'm guessing it seized, but not sure they're related. I'd like to know what the metal pieces are and what would be the next step to getting the crank bolt back on. Any help appreciated.