replacement/repair parts for Harbor Breeze fan

Last summer I installed a Harbor Breeze ceiling fan w/ light on my back porch (yes, it is rated for outdoor use). Somewhere along the line, we lost the two faster fan speeds. Thinking it would be a simple replacement of the pull-chain switch I opened it up, and found that the switch was hard-wired through a sealed plastic box that had melted bulges on one face and one edge. The Harbor Breeze web site is nothing more than a statement that Lowe's is their exclusive retailer, and a link to Lowe's site. Lowe's does not have a replacement. Does anyone know where I can get one? I would think this would really be a stock type part, and even though the original is all hard-wired, I could still cut'n'splice if I had the part.