Originally Posted by Shimpie
I'm guessing it's easier to push a fat column of air as opposed to a tall skinny column.
Actually it's the opposite. It is easier to push a skinny column of air, but it pumps less volume of air than a fatter column of the same height. The problem with your old pump was probably just a bad design in general.
To the O.P., try looking at pumps that are made to pump high pressures. The Silca Pista comes to mind.