I am not familiar with this type of mower so I don't want to suggest a way to straighten them. You can get replacements. go to www.sears.com, click on parts in top left side, click on lawn equipment on lower right side, type in model number and it will give you a parts list. You can order them online, check around to different sites because yuo might be able to get them cheaper. Also, if there is a sears parts store close to you, just go in with your model number and they can tell you what you'll need.
cholbach, June 2005