Townsend Seismic Sink Pump - where to find?

Yes, Rcprince is right. Just make sure it is a bicycle hand pump with a hose attachment. The tip used is a screw on presta valve.

Landru:
Rcprince is, IMO, correct about using a standard bicycle pump, but the problem will not be the pressure generated (as obviously you don't need much) but with the thread of the connector on the hose.

The new sinks (without the indicator light) and the older sinks (with the indicator light) have very different sized connectors where the air is pumped in (I have both). The newer sinks have a valve connection that is the same size as a normal automotive or bicycle inner tube. The older sinks have a connector that is much smaller.

For the newer sinks, a tire pump that uses a "clamp-on" type of hose connection should work ideally.

Reviving an old thread here.  I've got one of the older Seismic Sinks (with the indicator light).  Here's a solution to the pump issue:

The valve stem on the Sink is of the Dunlop type.  Purchase a Dunlop to Presta valve adapter or Dunlop to Schrader valve adapter and use a current model bicycle pump to pump up the unit. 

Works perfectly.