Wellhouse - Pressure Pump
The pump I use in my wellhouse is a Gould J15S
http://www.countrywatersystems.com/pdfs/gouldsshallowwelljetpump.pdf
The fire sprinkler system requires 26.34 GPM @ 46.203 PSI in the basement at the base of the riser. The base of the riser is about 20 feet above the pump in the wellhouse. Extrapolating from the spec table it looks like the official spec of the Gould J15S pump in my wellhouse is about 25.6 GPM @ 46.203 PSI, which is hopefully within allowable tolerance on the sprinkler test.
http://documentlibrary.xylemappliedwater.com/wp-content/blogs.dir/22/files/2012/07/BJS+-R1.pdf
http://www.grainger.com/product/GOULDS-WATER-TECHNOLOGY-Pump-1N439
http://www.lockewell.com/pdf/goulds/j-series.pdf
http://www.gpeltd.com/giconpumps/gpe/catalogs/products/technical/69.file1_content.gouldsjetpumps.pdf
http://documentlibrary.xylemappliedwater.com/wp-content/blogs.dir/22/files/2012/07/rjetparts.pdf
If you need a 2HP pump then here are some possibilities...
http://www.shoppumps.com/Goulds-1BF22012-End-Suction-Pump-1-phase-p/1bf22012.htm
http://www.shoppumps.com/Goulds-2BF22012-End-Suction-Pump-1-phase-p/2bf22012.htm
Here's a cheaper pump that is ok for a rain water system...