I'm not quite convinced it is a Kellogg, I need better pictures of the green pump. I can't quite identify it from that picture. The old pumps are great. They can be rebuilt many times, and simple/easy to work on. I would use the old pump, and put it on the red tank. Add a new Baldor motor, and your hotrod compressor will outrun any import from one of the home-improvement stores.
Here is a chart of Kellogg pumps.
http://aircompeq.com/ka.htm