Totally understandable, those lost stories are a hard thing to handle in these sorts of things. Though you should know that you appear to be missing the eighth serial off of William Hartnell's first season Reign of Terror.

Also, would it be possible to get standard width versions for season 16 and 23? Both seasons have been released completely and season 16 is only 6 discs and season 23 is only four discs. Thank you btw, this is an excellent set.