I have a Stanley lawnmower which I purchased during 2004 at Walmart. I have been told that it is an expensive Murray. It is whinning and will barely move when I hit the hydrostatic pedal. I was wondering if the hydrostatic module is worth replaceing or am I spending a lot on an old lawn mower. It cuts great, and runs great, but I don't want to spend over 550 on the repairs. Can I get parts? Is the pump repairable?