Since it sounds like a complete fence with 150 linear feet, plus the gates, and has been restored, a ball park figure based on salvaged fencing and gates would be $3,500 to $5,000. That would depend on how ornate the metal work is. Was the paint job based on existing remnants of original colors? I ask because that's an unusual paint scheme for 19th century fencing. It was usually black. If you have a provenance for it, you might be able to ask more.
Please let me know if I can be of further assistance with your conservation and preservation questions.