There's no set value on any older bags,
Coach or otherwise. You need to find a similar bag, which might not be easy since yours is in unused condition, at a site like Ebay and see what other bags of the same style sold for. We don't guesstimate selling prices here, like anything else on the secondary market, a preowned item is worth what someone else is willing to pay for it.
And before you sell any vintage bag you need to have it authenticated and identified, and you'll need to take and post photos. You can start at the Authenticate This Coach thread here in the Coach Shopping forum, read and follow the instructions in post number One of that thread.
https://forum.purseblog.com/threads/authenticate-this-coach-see-first-post-for-format.889527/
Then go to the LAST most recent page of posts and post your question and photos in the Reply box under the last post on that page.
Just so you know up front,
no selling, privately or otherwise, is allowed here at tPF so you'll have to decide on how and where you're going to sell it too.