How much will iphone 13 replacement of original LCD?

You can get an estimate for screen repair here:

iPhone Screen Repair & Replacement - Apple Support

The estimate I found for an iPhone 13 is: $ 279

That price is the estimate for apple directly, and can change based on the condition of the phone.

$29 (US) if the phone is still under AppleCare+.....and....the screen is defective (not physically damaged).