He may have gotten the model # wrong. There was a whole line of Pfaff Hobbymatics so you can probably get a good idea of what the machine is like from other models in the 800 & 900 range. It looks to me as if it may be what is considered a vintage machine. In that case you can get more info by joining a vintage Pfaff group on Yahoo. I checked Youtube, but could find only this short video of a Pfaff Hobbymatic sewing:
http://www.youtube.com/watch?v=AS_Pr8tDKg8