Here's a nice LP box set of Duke Ellington in the years 1938-1940:
I got a "near-mint" copy on Discogs for a low price.
It was issued by the Smithsonian institution, in 1976. An all star cast of jazz critics of the time contributed to the project: Martin Williams, Gunther Schuller, Dan Morgenstern...
There is a nice booklet with extensive liner notes, pictures, and credits.
The sound is good, better on some tracks, IMO, than some of the well known digital releases like the "Never No Lament" or "Centennial" CD box sets, but there are so many CD versions that you may find one you like. It's also nice to listen to these on vinyl while leafing through the booklet.
Here's a sample (it's simpler to make a video):
The same track on Qobuz in one of those CD version has some heavy distortion during the same solo:
Listen to Conga Brava by Duke Ellington and His Orchestra on Qobuz
https://open.qobuz.com/track/207295
The distortion was fixed in a more recent CD version, I believe, but not available on Qobuz, as far as I know. I have a Ben Webster compilation CD that has that track in pretty good sound, but this LP version is still a little more relaxing to listen to.