That seems right. Konohagakure was founded 80 years prior to current events (as said by Tobi when first met Sasuke). Nagato were born around 3rd Ninja War. Nagato was about 35-40 years old when he died. Madara looked like he was about 35-40 years old when he fought Hashirama. If he survived the battle against Hashirama it would make sense that he met Nagato (He was around 70-80 years old at that time) and died shortly from old age.
Madara mention that Nagato must have grown up, Nagato was a child during the 3 rd Ninja war were Jiraiya, Orochimaru and Tsunade were young adults and a team. That tells you their that it must have happen sometime after that.
Nagato was a child during the 2nd Shinobi World War and this is the war that Jirayai, Orochimaru and Tsunade became known as the Sannin. The 3rd Shinobi World War is when Minato became known as Konoha's Yellow Flash and we see this in the Kakashi Gaiden 2-part episodes. During the 3rd Shinobi War Nagato, Yahiko and Konan and that whole gang battled the Anzo twins, Hanzo and Danzo
I think Madara had to have died either shortly after his battle with the 1st or he was actually killed by the 1st. (Obviously I don't think Tobi is Madara). I believe this because in the latest chapter he says that he died shortly after receiving these eyes (Rinnegan), and I think if he had the Rinnegan during the battle he destroys the 1st Hokage or at least wins. If the OP is looking for an actual time well I think it has to be somewhere between 70-80 years ago because if the village was created 80 years ago and than they name Hashirama Hokage, Madara leaves the village hated by everyone and comes back sometime later with the Kyuubi under his control and the 1st fights him.
Then again I am going based off of what Tobi has said and I think that's all we can do since he is the only person who really goes into a good amount of detail about that time period/fight.
