Canceled AT&T TV / DIRECTV STREAM service

I recently canceled my directv stream service and am in the stages of boxing up 2 of the osprey units to find out that the remote(s) are missing.  I have 14 days to drop off to the local USPS.  What is the fee for the remotes that they’re going to charge me?

It’s for the osprey C71 KW-400 set top box