Any shots of Lloyd Bochner ?
I remember Bochner from season 2 of the original Dynasty, where he played Cecil Colby who died during a quickie marriage to Alexis (Joan Collins).
With the onset of the pandemic, ViacomCBS might have just manufactured less in its first run. They had no way of knowing whether sales of a giant 100+ discs set would sell at all via online retailers.
(So far I have not seen the Gunsmoke complete series set at any nearby wallyworlds, bestbuys...
Another possibility is the first run has sold out already, and ViacomCBS is still waiting for a new production run.
This might not be what folks on this thread/site want to hear, but I can't imagine this show being a huge priority for ViacomCBS when it comes to dvd releases.
With the pandemic...
I just did my weekly grocery shopping at the nearby wallyworld, and noticed they had the third set on the shelves.
It was season 8-9 set with 20 discs (according to the back cover).
I have only seen the first two sets in those giant 24+ discs cases. IIRC, the first set had seasons 1-4 and the second set had seasons 5-7 ?
(I have never seen the third set).