Pictures ?
Sight unseen it would be hard to tell, but it sounds like a working project, so anywhere between $500 - $650 for this title. It is a "drop target heaven" machine with awesome artwork. I'd say a working game (unrestored) would be around $750 and restored $1300 + (depending on the level of restoration).
Plastics are not available (NOS or Repro), and a replacement door, coin plate, scratch plate and hardware will set you back around AUS$200 (inc shipping as it is bulky). Chimes might be missing as well. So that's why a restored price will fluctuate. Sounds like the head is a bit dodgy, so a repaint may be required. Then you are looking at a resale price over $2000.
I'd offer $400 and work my way up, depending on the budget and more importantly, the condition.
What else in in the bulk deal