Suction limit on that type pump is 25'. Use the largest foot valve and pipe that will easily go into the casing.
hope it works out for you...Thank you for posting that link, The diagrams were very helpful. So it appears that a foot valve is not the correct application in a driven point. I should be installing a check valve between the end of the pipe and the well pump. Seems pretty simple and straight forward once i saw a picture. Thanks again