They usually go for $500 in my area for a complete set.
Missing weights can be found usually for about $20/$25 each except for cut out valve weights which are harder to come by.
Each pie weighs about 30/35 lbs for light weight 800 lbs for complete set and 40/45 lbs for HD weight 1160 lbs for complete set.
He sez all bolts included instead of all mounting hardware included. You might what to make sure he has the mounting adapters Nut/bolt.