Bilge Pump Replacement?

My bilge pump died last fall.  There are no markings on it so I have no idea what flow rate it is.  I know, just buy a big honkin' pump but that comes at a cost.  Any idea what a stock or standard GPH might have been?  Dont want to break the bank but dont want to wait two days to get the boat pumped out.

Might be a good time to wire in an automatic float switch (if none present). Not hard to wire. I mounted a pump and switch to an aluminum plate that rests securely on the floor (wooden Dunphy). No holes to drill. Works great, allows overnights in-water. 

All set with the auto switch.  Boat came with a water witch sensor (vs float) separate from the pump.  That died on my a couple years ago.  Since pump was fine, I didnt buy an automatic pump, and I didnt trust the water witch, so I picked up a basic float switch.  That is still fine, so I am just replacing the pump with one I had laying around.  What a pain.  I can see the designers at CC sitting around the table discussing this.  It went something like this.  So, we're building a boat that will last about 50 years.  Lets put in a $30 pump that is bound to die after about 10 years, and lets put it in before the engine. Then, lets put the engine in over top of it so it is absolutely impossible to get to.  And also, lets use this terrible thin, fragile brittle plastic tubing for the pipe outlet. That way, when its time to replace the pump (which is impossible) the tubing will break every 10 seconds in about 10 places while they try to get it hooked back up to the new pump.  Yup, great design.  All that being said, the pump you linked looks like a good deal for an 850 gph automatic pump.