I would highly recommend Fiorenza Bettini. She lives near Siena and can arrange a tour to your liking. You can reach her at https://gowithflotuscany.com/. We met her through her mother when we are in Tuscany in 2018. During the pandemic she held Zoom tours spotlighting local vendors. A few weeks ago, we were staying in Florence and I reached out to her to curate a trip for us. She worked on creating the perfect itinerary that combined history, architecture, food, and wine.
Since she works out of Siena, I would reach out to her to see if she can create a few hour tour from Siena. Note that if you do the Crete Senesi Drive (we did that on our own in 2018) and you stop and see anything, it is more than a few hours.