Free in Washington DC area, local pickup only:  A Mountain Computer
mark-sense card reader.  Has a DB-25 on the back and a bunch of dipswitches.
The DB-25 is RS-232.  Model 1100A.
Has a small hopper, rubber roller feed etc.  Maybe it could be refurbed
into a punch card reader.  No idea if it works or not.
E-mail me at "shoppa at trailing-edge.com" if interested.
Tim.