These questions mainly go to other users, not Best Buy or OEM. I can tell you that these can be sharpened at a knife/scissor sharpening store. Since this may be rare in your area (depending upon where you live), you may also find a farmer or metalworker that is used to working with tempered knives. They may be able to add life to your blade. Other than doing that, you might have to purchase the whole unit. I know the plastic gets brittle as it ages (mine cracked), so it may not be a bad idea to change the housing as well.