Rail Pass in Northern Honshu

We want to travel from Hokkaido down through Tohoku and N.Honshu to Tokyo.
Main stops are Hirosaki,Morioka,Matsushima,Aizuwakamatsu,Matsumoto,Kiso Valley. We have 16 days in Sept.
Is there a railpass we could use ?
We plan to rent a car at several of these places along the way to see the surrounding areas for a few days as we go.
Also, as we are over 60 is there a senior discount available?

JR Rail Pass is good throughout Japan on JR lines, buses, and ferries.

http://www.japanrailpass.net/eng/en003.html

or

http://www.japan-guide.com/e/e2357.html

I can't see details of the 3 day pass I've been told about for September.
Is there any information on this available?

Here's the JR East page on it:

http://www.jreast.co.jp/e/eastpass_sp/index.html

Thanks,that's very useful for us.