This one is tough but if you're lucky, you can find them.
I had to rip my own DVD sets of Kids in the Hall and Mr. Show.
I got really fuckin lucky when I found copies of Get A Life.
I've had halfway decent luck with Soulseek with more obscure shit (like Get A Life was found on Soulseek), but a lot of people on there have their collections locked up and only want to "trade rare shit" and if you don't have rare shit they want, you can kick rocks. I fucking hate it, because it's the antithesis of what piracy is supposed to be, which is freely sharing. These guys have turned it into a retro collection competition and it sucks.
I use SabNZBD, Eweka.nl, and nzbgeek. It's about $70/yr or so for the two subscriptions.
You will configure the download client to use the provider for its connection, but the nzbs you download will tell your client which messages contain the files.
You can search the indexer and download files that way as if you were using a torrent site. But it is really smooth and easy to use with sonarr or radarr fetching things for you. In that case, you would configure those fetchers to log into the indexer to search then send the NZB to your client automatically.
I use a Tablo OTA DVR and there is a Tablo Ripper app that I use to pull the MP4's out of it (sadly not a feature they offer). Then I use MCE Buddy to remove commercials. So your suggestion is legit.
my co-worker wants an ota dvr. what one do you have? and is it easy to use for someone that can barely navigate a tv menu? ease of use and minimal internet bandwidth use (they use a 'jetpack' with crappy signal for internet at home) are their main requirements.