Barring any security issues from your office: I use the 1300 scan snap which might be helpful to you since it is small and designed to be portable.
I would scan everything into Evernote, and use folder just like in your file cabinet. If you like you could make the whole 43 folder, tickler file for Evernote. OR you could use: http://www.followupthen.com/
If there are security issues, then you need to have an open and honest talk with your bosses about whether both these things can exist: not having an in office storage space and whatever level of security you have.
I'm sure there are security concerns with using Evernote, but I know at least 2 of our security guys use it, and the Bring Your Own Device survey I did specifically asked how important Evernote access was to me.
I just found out there is a app for Android which will take a picture directly to PDF. That might be worth looking at.