One source for Rumours of the Upper River that may be worth adding, as a pre-railway source, is from graduating Visionary Students from your Laboratory! You get one per Visionary Student graduated, without having to spend resources like with other pre-railway means of getting the Rumours, if you've raised your Teaching Reputation in the Laboratory high enough to access the Visionary Student.

I'd add it myself, but I've never edited a wiki before and don't wanna mess anything up, haha ^^;