1964.5 Mustang 289

Update on previous post, still thoughts on fair purchase price? Test drove today, ordered 7500 to an answer of no and walk away. Came back around and said there’s no rush we can negotiate further another day, neither of us are in a rush to sell or buy. Thoughts? 400k+ on dash, 40k+ on rebuild motor. Also noticed and was mentioned the “radiator overflow” was eliminated by someone? Something leaks into the passenger footing area.