Sweet bike!
The condition is fantastic. Unfortunately a Simplex bike won't sell as high as a Campagnolo bike. Personally, I wouldn't accept anything under than $1500 for it. On a lucky day on ebay you may break $2500. You just need a few motivated buyers.
I'd like to see pics of the hubs. Siamt? I am also curious about the handlebars and levers. I think the cockpit may have been changed over the years. And a picture of the headset would be nice, should be marked Frejus.