If you're willing to take things into your own hands, you could try polishing the screen to remove the scratch. Some companies sell a cheap paste and cloth that's supposed to be able to remove scratches.

WARNING: I have never done this, and I have no idea if this will destroy your screen. There seem to be some concerns about whether this kind of polish will work on a touch screen. I wasn't able to find a definitive answer about if it is safe to do or not on a touchscreen. However, it will be much cheaper than replacing the screen. I strongly recommend doing a lot of research before trying this.

If you try this, please report back with the results.

Here are some links:

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