Sometimes U can go to a RV store and they have used pumps from old junker trailers that they have taken in trade that they just strip for parts!! U might be able to get a pump pretty reasonable...but don't go and buy one new from the RV place they won't even kiss U when they done!! a hardware store would be better, or a Ag supply store that sells portable sprayer parts!!! these 12V pressure regulated pumps are fairly common, but have a wide range in pricing for the same pump depending on where U buy it..