Fortunately, all of these missing episodes exist as audio recordings made by viewers of the original broadcasts.
Commercial novelizations exist for all serials with missing episodes.
These novelizations are predominantly inaccurate and highly embellished making them unsuitable for the purpose of academic research into the original broadcasts. These novelizations and transcriptions are now out of print, though they can be obtained from collectibles dealers. Who Links page has a lengthy listing of such dealers. Who Scripts Project was initated to provide transcriptions of the audio recordings of all episodes that no longer exist on video or film. The Project has since realized this goal.