Rattling alternator

Hello all

After a month of vacation I finally got my Z back on the road. After hooking the battery back up I fired her up. She started as if I had never left. Walking around the engine bay I noticed that the alternator rattles (or wobbles would be a better word) From the looks there are two bolts holding it to the engine.

Two questions.

1. Should there be more bolts holding it on? There is a clear hold on the back side of the alternator nearest the engine. (not on the little track)

2. If the bolt had broken, does anyone know what kind and where one could find a bolt?

Jan