Where are these "jack stabilizer" backhoes?

Back when I was 5 years old, I saw........ Case, Cat, Deere, JCB, Hitachi, and Komatsu backhoes, as well as backhoes with........ "jack type" stabilizers (at least that's what the book "Dazzling Diggers" calls them). I wish I had a picture to show you what I'm talking about, but........ When I turned 6, the JCB and jack stabilizer backhoes began to disappear. And by the time I was 7, they were all gone! .............Where are they now????? Like..... Uhhh..... Case made a new "T-Series" backhoe, which is a jack stabilizer version of the Super N Case backhoes, only.................. It's not appearing around here! And also, JCB still makes backhoes as of today. Because 2 years ago, I witnessed in person for the first time in 16 years, a JCB 4CX backhoe. And that 4CX backhoe looked like it's up to date. However, that JCB backhoe I mentioned did not have the jack stabilizer configuration. So that's that mystery still unsolved.

If you mean where the stabilizer goes straight down instead of pivoting then there are still plenty around... certain municipalities like then for street work as they are more 'compact' for work in traffic but they are also less stable and not as productive.

I actually have one in the front yard

I think the image below is what you are describing. These are called "Side shift" backhoes. As Ronsii says; made for compact areas. Imagine digging along a wall, normal outriggers would have nowhere to go.

Most of the JCB backhoes sold in Europe have the side shift backhoe. Here in NA JCB sells the 3CX Compact (formally the 2CX or 212s) which has the side shift backhoe. But it is smaller (around 12.4k lbs) than a Case 580. NA more open construction sites vs Europe.

and if you are bored I recently posted this video of me rebuilding the side shift stabilizers on my JCB

Yes! That's it! And those JCB backhoes look like they're up to date. More proof JCB still makes backhoes.

I was a service manager for a dealer who handled JCB a bunch of years ago. The only good thing about the brand was the factory service rep. Great guy with a heck of a sense of humor. The brand though and their loader backhoes were probably the worst in the world in those days and the factory never honored a warranty at the contracted value. I rank them as about the same as a Terex with worse parts support.