I'd western union her the money before anyone else sees the ad and beats you to it. She'll probably ship it for free using her military contacts. I'm sure it belonged to her deceased ex husband, and it makes her sad every time she sees it; she just wants it gone to someone who will appreciate it.
Obviously too good to be true. If the tool box was in my neighborhood and I needed it or it's contents, I would only buy it if I could examine it personally and take it with me after exchanging cash.