Your best bet on ordering a replacement motor for Master Flow PR3X is to get it directly from Master Flow, a division of GAF. If you have your original paperwork, there is a 10 year warranty and it should be no cost for the part just shipping. The replacement motor can be purchased by calling 1-877-423-2665 (Master Flow customer service) for $74.48 including shipping. Their website is gaf.com and you will find their contact page at www.gaf.com/Corporate-Information/Contact-GAF/Contact-GAF.as