ceriobaby,
With no photos of your Series 7 chairs an intelligent valuation is not possible. Also, the forum guidelines prohibit such activities (valuations and offers of sale).
The search of current popular venues such as , eBay and other sellers possibly more specific to your location, should provide reasonable estimates to the Series 7 chairs asking price and actual selling price.
Best wishes in finding a suitable resale price and future sale of your Series 7 chairs.
If you need any help, please contact us at – info@designaddict.com